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Update C++ style guide to 3.146: - Make the messaging on DISALLOW_EVIL_CONSTRUCTORS more clear that we should not be rewriting old code but should simply prefer DISALLOW_COPY_AND_ASSIGN on new code. - s/Initializer Lists/Constructor Initializer Lists/ since people search for this based on knowing it's part of the constructor, but forget the precise name. - Allow data members in a test fixture to be private. - Loosen restrictions on globals. - Add explicit guideline for nested namespace formatting. - Strengthen the prohibition against operator overloading for operator&. - Add recommendation for "_" over "-" in file names. - Revise the "Copy Constructors" section for brevity and clarity. Emphasize preference for standard over nonstandard copy operations. - Weaken the wording at the top of the "Doing Work in Constructors" section, making it clear that Init() methods are not absolutely required for non-trivial initialization. - Fix minor typos and grammatical errors. Update Objective-C style guide to 2.14: - Add the Rule of Four for indenting parameters. Allow either of two forms for formatting methods with short first keywords. - Update the guidance on BOOL vs. bool. - Whitespace cleanup. Update Python style guide to 2.14: - Consolidate discussion of the string module, apply, map, filter, and reduce into a single section. - Make it explicit that functions and classes can be nested inside methods.
2009-10-24 05:01:49 +08:00
<HTML xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcq="http://purl.org/dc/qualifiers/1.0/" xmlns:fo="http://www.w3.org/1999/XSL/Format" xmlns:fn="http://www.w3.org/2005/xpath-functions">
A pyguide.html
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<HEAD>
<TITLE>Google Python Style Guide</TITLE>
Update C++ style guide to 3.171: - Add a section to specify deprecation comments.
2010-08-11 02:40:41 +08:00
<META http-equiv="Content-Type" content="text/html; charset=utf-8">
A pyguide.html
2009-07-24 04:09:56 +08:00
<LINK HREF="http://www.google.com/favicon.ico" type="image/x-icon" rel="shortcut icon">
<LINK HREF="styleguide.css" type="text/css" rel="stylesheet">
<SCRIPT language="javascript" type="text/javascript">
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
function GetElementsByName(name) {
// Workaround a bug on old versions of opera.
A pyguide.html
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if (document.getElementsByName) {
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
return document.getElementsByName(name);
A pyguide.html
2009-07-24 04:09:56 +08:00
} else {
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
return [document.getElementById(name)];
A pyguide.html
2009-07-24 04:09:56 +08:00
}
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
}
/**
* @param {string} namePrefix The prefix of the body name.
* @param {function(boolean): boolean} getVisibility Computes the new
* visibility state, given the current one.
*/
function ChangeVisibility(namePrefix, getVisibility) {
var bodyName = namePrefix + '__body';
var buttonName = namePrefix + '__button';
var bodyElements = GetElementsByName(bodyName);
var linkElement = GetElementsByName('link-' + buttonName)[0];
A pyguide.html
2009-07-24 04:09:56 +08:00
if (bodyElements.length != 1) {
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
throw Error('ShowHideByName() got the wrong number of bodyElements: ' +
bodyElements.length);
A pyguide.html
2009-07-24 04:09:56 +08:00
} else {
var bodyElement = bodyElements[0];
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
var buttonElement = GetElementsByName(buttonName)[0];
var isVisible = bodyElement.style.display != "none";
if (getVisibility(isVisible)) {
A pyguide.html
2009-07-24 04:09:56 +08:00
bodyElement.style.display = "inline";
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
linkElement.style.display = "block";
A pyguide.html
2009-07-24 04:09:56 +08:00
buttonElement.innerHTML = '▽';
} else {
bodyElement.style.display = "none";
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
linkElement.style.display = "none";
A pyguide.html
2009-07-24 04:09:56 +08:00
buttonElement.innerHTML = '▶';
}
}
}
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
function ShowHideByName(namePrefix) {
ChangeVisibility(namePrefix, function(old) { return !old; });
}
function ShowByName(namePrefix) {
ChangeVisibility(namePrefix, function() { return true; });
}
A pyguide.html
2009-07-24 04:09:56 +08:00
function ShowHideAll() {
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
var allButton = GetElementsByName("show_hide_all_button")[0];
A pyguide.html
2009-07-24 04:09:56 +08:00
if (allButton.innerHTML == '▽') {
allButton.innerHTML = '▶';
SetHiddenState(document.getElementsByTagName("body")[0].childNodes, "none", '▶');
} else {
allButton.innerHTML = '▽';
SetHiddenState(document.getElementsByTagName("body")[0].childNodes, "inline", '▽');
}
}
// Recursively sets state of all children
// of a particular node.
function SetHiddenState(root, newState, newButton) {
for (var i = 0; i != root.length; i++) {
SetHiddenState(root[i].childNodes, newState, newButton);
if (root[i].className == 'showhide_button') {
root[i].innerHTML = newButton;
}
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
if (root[i].className == 'stylepoint_body' ||
root[i].className == 'link_button') {
A pyguide.html
2009-07-24 04:09:56 +08:00
root[i].style.display = newState;
}
}
}
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
function EndsWith(str, suffix) {
var l = str.length - suffix.length;
return l >= 0 && str.indexOf(suffix, l) == l;
}
function RefreshVisibilityFromHashParam() {
var hashRegexp = new RegExp('#([^&#]*)$');
var hashMatch = hashRegexp.exec(window.location.href);
var anchor = hashMatch && GetElementsByName(hashMatch[1])[0];
var node = anchor;
var suffix = '__body';
while (node) {
var id = node.id;
var matched = id && EndsWith(id, suffix);
if (matched) {
var len = id.length - suffix.length;
Update C++ style guide to 3.231: - Clarify that sentence-like non-sentence comments are permitted. - Note that older code with incorrect #include ordering should be fixed. - Revamp the section on default function arguments. - Avoid explicitly recommending Init() methods. - C++11: permit "auto". - C++11: permit ">>" in place of "> >". - C++11: permit range-based "for". - C++11: permit variadic macros (already permitted as a C++03 extension). - C++11: permit "LL" and "ULL" literal suffixes (already permitted as a C++03 extension). - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - C++11: permit new features in <algorithm> and the portion of <numeric> that does not require initializer lists. - Revise rules on forward declarations: explicitly forbid forward-declared functions, do not mandate forward declarations, discourage forward-declared templates. - Remove the rule requiring "const" qualifiers for member functions to be on the same line as the closing parenthesis of the parameter list. - Fix typo: "unnamed namespaces." - C++11: permit local types as template parameters. - Fix typo: "unfamiliar." - Relax RTTI rules to permit its use, but warn about its abuse. - C++11: permit nullptr and nullptr_t. Revise text referring to NULL to refer more generically to null pointers. - Remove the "don't go crazy with const" rule. - Fix typo: "dir/foo2" should bee "dir2/foo2." - Remove reference to a specific GCC version. Update Objective-C style guide to 2.48: - Revise method declaration and invocation formatting rules for long names. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. Top-of-file comments are not required. - Fix dead link in the "nil Checks" section. - Cover ARC. - Specify that @private is only required for instance variables in header files. - Permit NSNumber literals. - Change the naming convention for instance variables from trailing underscore to leading underscore, allowing a wide exception for existing code and projects. - Fix description of BOOL with respect to its signedness. Update Python style guide to 2.45: - Recommend "pylint: disable" over "pylint: disable-msg." - Fix case-sensitive anchor. - Provide a better explanation of the problems with catch-all "except:." - Permit "map" and "filter" in absence of inlined lambdas. Update JavaScript style guide to 2.64: - Clarify rules for requiring and providing inner dependencies on classes. - Clarify semicolons for functions. - Note proper namespace and filename casing. - Fix typos: "@extends." - Permit parentheses to be omitted on unions. - Don't require method descriptions when obvious. - "in" is a keyword, put it in <code>. - New "Aliasing with goog.scope" section. - Rewrite the "Constants" section. - Remove the recommendation to use join() to build strings. - Add the "@expose" annotation. - Fix the "@suppress" example. - Remove reference alternate cast syntax. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - Say that "use strict" is not required. - Fix links to "optional" section. - Rewrite "JavaScript Types" section. - Fix typos: "parameterizes," "converted." - Prefer in-constructor field initialization. - Add a section on "delete" and null-assignment. - Add a note about optional JSDoc comments on enum values. - State explicitly that dot operators belong at the ends of lines. - Add "@dict" and "@struct" annotations. - Add links to the JavaScript Types section. - Require (rather than encourage) compiling. Update HTML/CSS style guide to 2.19: - Rephrased quotation guidelines. - Updated W3C I18N article reference. - Fixed revision number. Update styleguide.xsl to 1.34: - Fix error in RefreshVisibilityFromHashParam when a URL fragment points to a named anchor within a section, as used by the JavaScript style guide.
2012-11-29 04:26:27 +08:00
ShowByName(id.substring(0, len));
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
if (anchor.scrollIntoView) {
anchor.scrollIntoView();
A pyguide.html
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}
Update C++ style guide to 3.231: - Clarify that sentence-like non-sentence comments are permitted. - Note that older code with incorrect #include ordering should be fixed. - Revamp the section on default function arguments. - Avoid explicitly recommending Init() methods. - C++11: permit "auto". - C++11: permit ">>" in place of "> >". - C++11: permit range-based "for". - C++11: permit variadic macros (already permitted as a C++03 extension). - C++11: permit "LL" and "ULL" literal suffixes (already permitted as a C++03 extension). - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - C++11: permit new features in <algorithm> and the portion of <numeric> that does not require initializer lists. - Revise rules on forward declarations: explicitly forbid forward-declared functions, do not mandate forward declarations, discourage forward-declared templates. - Remove the rule requiring "const" qualifiers for member functions to be on the same line as the closing parenthesis of the parameter list. - Fix typo: "unnamed namespaces." - C++11: permit local types as template parameters. - Fix typo: "unfamiliar." - Relax RTTI rules to permit its use, but warn about its abuse. - C++11: permit nullptr and nullptr_t. Revise text referring to NULL to refer more generically to null pointers. - Remove the "don't go crazy with const" rule. - Fix typo: "dir/foo2" should bee "dir2/foo2." - Remove reference to a specific GCC version. Update Objective-C style guide to 2.48: - Revise method declaration and invocation formatting rules for long names. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. Top-of-file comments are not required. - Fix dead link in the "nil Checks" section. - Cover ARC. - Specify that @private is only required for instance variables in header files. - Permit NSNumber literals. - Change the naming convention for instance variables from trailing underscore to leading underscore, allowing a wide exception for existing code and projects. - Fix description of BOOL with respect to its signedness. Update Python style guide to 2.45: - Recommend "pylint: disable" over "pylint: disable-msg." - Fix case-sensitive anchor. - Provide a better explanation of the problems with catch-all "except:." - Permit "map" and "filter" in absence of inlined lambdas. Update JavaScript style guide to 2.64: - Clarify rules for requiring and providing inner dependencies on classes. - Clarify semicolons for functions. - Note proper namespace and filename casing. - Fix typos: "@extends." - Permit parentheses to be omitted on unions. - Don't require method descriptions when obvious. - "in" is a keyword, put it in <code>. - New "Aliasing with goog.scope" section. - Rewrite the "Constants" section. - Remove the recommendation to use join() to build strings. - Add the "@expose" annotation. - Fix the "@suppress" example. - Remove reference alternate cast syntax. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - Say that "use strict" is not required. - Fix links to "optional" section. - Rewrite "JavaScript Types" section. - Fix typos: "parameterizes," "converted." - Prefer in-constructor field initialization. - Add a section on "delete" and null-assignment. - Add a note about optional JSDoc comments on enum values. - State explicitly that dot operators belong at the ends of lines. - Add "@dict" and "@struct" annotations. - Add links to the JavaScript Types section. - Require (rather than encourage) compiling. Update HTML/CSS style guide to 2.19: - Rephrased quotation guidelines. - Updated W3C I18N article reference. - Fixed revision number. Update styleguide.xsl to 1.34: - Fix error in RefreshVisibilityFromHashParam when a URL fragment points to a named anchor within a section, as used by the JavaScript style guide.
2012-11-29 04:26:27 +08:00
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
return;
A pyguide.html
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}
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
node = node.parentNode;
}
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window.onhashchange = RefreshVisibilityFromHashParam;
A pyguide.html
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Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
window.onload = function() {
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var showOneValue = showOneRegex.exec(window.location.href);
if (showOneValue) {
ShowHideByName(showOneValue[2]);
A pyguide.html
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}
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
RefreshVisibilityFromHashParam();
A pyguide.html
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<BODY>
<H1>Google Python Style Guide</H1>
<p align="right">
Update C++ style guide to 3.245: - Relax the rule for sizeof(varname) vs. sizeof(type). - Allow an exception for nonconst reference parameters where convention dictates their use, such as for swap. - C++11: allow static_assert. - Require non-trivial fall-through between cases in switch statements to be annotated. Trivial fall-through includes consecutive case labels with no intervening code, and no comment is required in these cases. - C++11: allow constexpr. - Revise the "Integer Types" section to note type-width problems. - Clarify that the "arguments on subsequent lines" function call style is acceptable even when the 80-column limit doesn't require it. - Boost: allow part of Polygon. - C++11: allow <tuple>. Update Objective-C style guide to 2.52: - Fix ARC example to not imply the use of @private in .m files. - Add an example to the "Category Names" section. - Require that ARC-using files insert preprocessor directives that generate an error when compiling without ARC. - Fix spacing around the *s in the ARC example per the C++ style guide. Update Python style guide to 2.48: - Allow comments with URLs to exceed 80 characters per line. - Update outdated implicit-line-joining URLs. Update HTML/CSS style guide to 2.21: - Consistent use of title case. - Add new "Declaration Block Separation" section. - Add a CSS example to the "Capitalization" section. - Minor fixes to whitespace. Update JavaScript style to guide to 2.72: - Make it clear that the injunction against aliasing namespaces only applies to local aliases, not goog.scope. - Clarify the style guide's recommendation on array/object literals. - Add documentation on @private {type}, @protected {type}, and @const {type}. - Make JSDoc descriptions required only if not obvious. - Clarify that only private properties and methods need a trailing underscore. - Fix spelling of arv's name. Update Common Lisp style guide to 1.18: - Macro-defining macros are harder to understand for everyone, not just for the "uninitiated." There's no need to condescend. In all of the above style guides: - The guide source is now encoded as UTF-8. The numeric character references have been replaced with raw UTF-8-encoded characters.
2013-03-22 00:03:26 +08:00
Revision 2.48
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</p>
<address>
Amit Patel<br>
Antoine Picard<br>
Eugene Jhong<br>
Jeremy Hylton<br>
Matt Smart<br>
Mike Shields<br>
</address>
<DIV style="margin-left: 50%; font-size: 75%;">
<P>
Each style point has a summary for which additional information is available
by toggling the accompanying arrow button that looks this way:
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="showhide_button" style="margin-left: 0; float: none">▶</SPAN>.
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You may toggle all summaries with the big arrow button:
</P>
<DIV style=" font-size: larger; margin-left: +2em;">
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="showhide_button" style="font-size: 180%; float: none" onclick="javascript:ShowHideAll()" name="show_hide_all_button" id="show_hide_all_button">▶</SPAN>
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Toggle all summaries
</DIV>
</DIV>
<DIV class="toc">
<DIV class="toc_title">Table of Contents</DIV>
<TABLE>
<TR valign="top" class="">
<TD><DIV class="toc_category"><A href="#Python_Language_Rules">Python Language Rules</A></DIV></TD>
<TD><DIV class="toc_stylepoint">
Updating python style guide
2012-09-19 07:16:02 +08:00
<SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#pychecker">pychecker</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Imports">Imports</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Packages">Packages</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Exceptions">Exceptions</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Global_variables">Global variables</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Nested/Local/Inner_Classes_and_Functions">Nested/Local/Inner Classes and Functions</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#List_Comprehensions">List Comprehensions</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Default_Iterators_and_Operators">Default Iterators and Operators</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Generators">Generators</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Lambda_Functions">Lambda Functions</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Conditional_Expressions">Conditional Expressions</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Default_Argument_Values">Default Argument Values</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Properties">Properties</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#True/False_evaluations">True/False evaluations</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Deprecated_Language_Features">Deprecated Language Features</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Lexical_Scoping">Lexical Scoping</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Function_and_Method_Decorators">Function and Method Decorators</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Threading">Threading</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Power_Features">Power Features</A></SPAN> </DIV></TD>
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</TR>
<TR valign="top" class="">
<TD><DIV class="toc_category"><A href="#Python_Style_Rules">Python Style Rules</A></DIV></TD>
<TD><DIV class="toc_stylepoint">
Updating python style guide
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<SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Semicolons">Semicolons</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Line_length">Line length</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Parentheses">Parentheses</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Indentation">Indentation</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Blank_Lines">Blank Lines</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Whitespace">Whitespace</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Shebang_Line">Shebang Line</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Comments">Comments</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Classes">Classes</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Strings">Strings</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Files_and_Sockets">Files and Sockets</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#TODO_Comments">TODO Comments</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Imports_formatting">Imports formatting</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Statements">Statements</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Access_Control">Access Control</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Naming">Naming</A></SPAN> <SPAN style="padding-right: 1em; white-space:nowrap;" class=""><A href="#Main">Main</A></SPAN> </DIV></TD>
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</TR>
</TABLE>
</DIV>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class="">
<H2 name="Important_Note" id="Important_Note">Important Note</H2>
<DIV class="">
<H3><A name="Displaying_Hidden_Details_in_this_Guide" id="Displaying_Hidden_Details_in_this_Guide">Displaying Hidden Details in this Guide</A></H3>
Update Python style guide with styleguide.xsl r51.
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<SPAN class="link_button" id="link-Displaying_Hidden_Details_in_this_Guide__button" name="link-Displaying_Hidden_Details_in_this_Guide__button"><A href="?showone=Displaying_Hidden_Details_in_this_Guide#Displaying_Hidden_Details_in_this_Guide">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Displaying_Hidden_Details_in_this_Guide')" name="Displaying_Hidden_Details_in_this_Guide__button" id="Displaying_Hidden_Details_in_this_Guide__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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This style guide contains many details that are initially
hidden from view. They are marked by the triangle icon, which you
see here on your left. Click it now.
You should see "Hooray" appear below.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Displaying_Hidden_Details_in_this_Guide__body" id="Displaying_Hidden_Details_in_this_Guide__body" style="display: none">
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<p>
Hooray! Now you know you can expand points to get more
details. Alternatively, there's a "toggle all" at the
top of this document.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</DIV></DIV>
</DIV>
</DIV>
<DIV class="">
<H2 name="Background" id="Background">Background</H2>
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<p>
Python is the main scripting language used at Google. This
style guide is a list of <em>do</em>s and <em>don't</em>s for Python
programs.
</p>
New file google_python_style.vim.
2010-11-30 04:32:06 +08:00
<p>
To help you format code correctly, we've created a <a href="google_python_style.vim">settings
file for Vim</a>. For Emacs, the default settings should be fine.
</p>
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Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
A pyguide.html
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Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class="">
<H2 name="Python_Language_Rules" id="Python_Language_Rules">Python Language Rules</H2>
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Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class="">
<H3><A name="pychecker" id="pychecker">pychecker</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-pychecker__button" name="link-pychecker__button"><A href="?showone=pychecker#pychecker">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('pychecker')" name="pychecker__button" id="pychecker__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Run <code>pychecker</code> over your code.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
Updating python style guide
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<DIV class=""><DIV class="stylepoint_body" name="pychecker__body" id="pychecker__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
PyChecker is a tool for finding bugs in Python source code. It finds
problems that are typically caught by a compiler for less dynamic
languages like C and C++. It is similar to lint. Because of the
dynamic nature of Python, some warnings may be incorrect; however,
spurious warnings should be fairly infrequent.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Catches easy-to-miss errors like typos, use-vars-before-assignment, etc.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
<code>pychecker</code> isn't perfect. To take
advantage of it, we'll need to sometimes: a) Write around it b)
Suppress its warnings c) Improve it or d) Ignore it.
</P>
<P class="">
Updating python style guide
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<SPAN class="stylepoint_section">Decision: </SPAN>
A pyguide.html
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Make sure you run <code>pychecker</code> on your code.
</P>
<p>
For information on how to run <code>pychecker</code>, see the
<a HREF="http://pychecker.sourceforge.net">pychecker
homepage</a>
</p>
<p>
To suppress warnings, you can set a module-level variable named
Updating python style guide
2012-09-19 07:16:02 +08:00
<code>__pychecker__</code> to suppress appropriate warnings.
A pyguide.html
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For example:
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE>
<span class="external"></span>__pychecker__ = 'no-callinit no-classattr'</PRE></DIV>
A pyguide.html
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<p>
Suppressing in this way has the advantage that we can easily search
for suppressions and revisit them.
</p>
<p>
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You can get a list of pychecker warnings by doing
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<code>pychecker --help</code>.
</p>
<p>
Unused argument warnings can be suppressed by using `_' as the
identifier for the unused argument or prefixing the argument name with
`unused_'. In situations where changing the argument names is
infeasible, you can mention them at the beginning of the function.
For example:
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>def foo(a, unused_b, unused_c, d=None, e=None):
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<span class="external"> </span>_ = d, e
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<span class="external"> </span>return a
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</PRE></DIV>
A pyguide.html
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<p>
Ideally, pychecker would be extended to ensure that such `unused
declarations' were true.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Imports" id="Imports">Imports</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Imports__button" name="link-Imports__button"><A href="?showone=Imports#Imports">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Imports')" name="Imports__button" id="Imports__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Use <code>import</code>s for packages and modules only.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Imports__body" id="Imports__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
Reusability mechanism for sharing code from one module to another.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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The namespace management convention is simple. The source of each
identifier is indicated in a consistent way; <code>x.Obj</code> says
that object <code>Obj</code> is defined in module <code>x</code>.
A pyguide.html
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</P>
<P class="">
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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<SPAN class="stylepoint_section">Cons: </SPAN> Module names can still collide. Some module names are
inconveniently long.
A pyguide.html
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</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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Use <code>import x</code> for importing packages and modules.
<br>
Use <code>from x import y</code> where <code>x</code> is
the package prefix and <code>y</code> is the module name with no
prefix.
<br>
Use <code>from x import y as z</code> if two modules named
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
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<code>y</code> are to be imported or if <code>y</code> is an
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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inconveniently long name.
</P>
For example the module
<code>sound.effects.echo</code> may be imported as follows:
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>from sound.effects import echo
<span class="external"></span>...
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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<span class="external"></span>echo.EchoFilter(input, output, delay=0.7, atten=4)
A pyguide.html
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<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</PRE></DIV>
A pyguide.html
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<p>
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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Do not use relative names in imports. Even if the module is in the
same package, use the full package name. This helps prevent
unintentionally importing a package twice.
A pyguide.html
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</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Packages" id="Packages">Packages</A></H3>
Update Python style guide with styleguide.xsl r51.
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<SPAN class="link_button" id="link-Packages__button" name="link-Packages__button"><A href="?showone=Packages#Packages">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Packages')" name="Packages__button" id="Packages__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
2010-11-24 02:02:36 +08:00
Import each module using the full pathname location of the module.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Packages__body" id="Packages__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Avoids conflicts in module names. Makes it easier to find modules.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
Makes it harder to deploy code because you have to replicate the
package hierarchy.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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All new code should import each module by its full package name.
A pyguide.html
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</P>
<p>
Imports should be as follows:
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE># Reference in code with complete name.
A pyguide.html
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import sound.effects.echo
Update C++ style guide to 3.180: - Remove comment about naming macros like enums. - Move a bad code snippet from a CODE_SNIPPET to a BAD_CODE_SNIPPET element. Update Python style guide to 2.18: - Clarify the syntax for import statements. Update styleguide.xsl to 1.31: - Substitute underscore for apostrophe in anchor names.
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# Reference in code with just module name (preferred).
A pyguide.html
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from sound.effects import echo
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Exceptions" id="Exceptions">Exceptions</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Exceptions__button" name="link-Exceptions__button"><A href="?showone=Exceptions#Exceptions">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Exceptions')" name="Exceptions__button" id="Exceptions__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Exceptions are allowed but must be used carefully.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Exceptions__body" id="Exceptions__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
Exceptions are a means of breaking out of the normal flow of control
of a code block to handle errors or other exceptional conditions.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
The control flow of normal operation code is not cluttered by
error-handling code. It also allows the control flow to skip multiple
frames when a certain condition occurs, e.g., returning from N
nested functions in one step instead of having to carry-through
error codes.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
May cause the control flow to be confusing. Easy to miss error
cases when making library calls.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Exceptions must follow certain conditions:
<ul>
Updating python style guide
2012-09-19 07:16:02 +08:00
<li>Raise exceptions like this: <code>raise MyException('Error
message')</code> or <code>raise MyException</code>. Do not
use the two-argument form (<code>raise MyException, 'Error
message'</code>) or deprecated string-based exceptions
(<code>raise 'Error message'</code>).</li>
A pyguide.html
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<li>Modules or packages should define their own domain-specific
base exception class, which should inherit from the built-in
Exception class. The base exception for a module should be called
<code>Error</code>.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>class Error(Exception):
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<span class="external"> </span>pass</PRE></DIV>
A pyguide.html
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</li>
<li>Never use catch-all <code>except:</code> statements, or
catch <code>Exception</code> or <code>StandardError</code>,
unless you are re-raising the exception or in the outermost
block in your thread (and printing an error message). Python
is very tolerant in this regard and <code>except:</code> will
Update C++ style guide to 3.231: - Clarify that sentence-like non-sentence comments are permitted. - Note that older code with incorrect #include ordering should be fixed. - Revamp the section on default function arguments. - Avoid explicitly recommending Init() methods. - C++11: permit "auto". - C++11: permit ">>" in place of "> >". - C++11: permit range-based "for". - C++11: permit variadic macros (already permitted as a C++03 extension). - C++11: permit "LL" and "ULL" literal suffixes (already permitted as a C++03 extension). - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - C++11: permit new features in <algorithm> and the portion of <numeric> that does not require initializer lists. - Revise rules on forward declarations: explicitly forbid forward-declared functions, do not mandate forward declarations, discourage forward-declared templates. - Remove the rule requiring "const" qualifiers for member functions to be on the same line as the closing parenthesis of the parameter list. - Fix typo: "unnamed namespaces." - C++11: permit local types as template parameters. - Fix typo: "unfamiliar." - Relax RTTI rules to permit its use, but warn about its abuse. - C++11: permit nullptr and nullptr_t. Revise text referring to NULL to refer more generically to null pointers. - Remove the "don't go crazy with const" rule. - Fix typo: "dir/foo2" should bee "dir2/foo2." - Remove reference to a specific GCC version. Update Objective-C style guide to 2.48: - Revise method declaration and invocation formatting rules for long names. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. Top-of-file comments are not required. - Fix dead link in the "nil Checks" section. - Cover ARC. - Specify that @private is only required for instance variables in header files. - Permit NSNumber literals. - Change the naming convention for instance variables from trailing underscore to leading underscore, allowing a wide exception for existing code and projects. - Fix description of BOOL with respect to its signedness. Update Python style guide to 2.45: - Recommend "pylint: disable" over "pylint: disable-msg." - Fix case-sensitive anchor. - Provide a better explanation of the problems with catch-all "except:." - Permit "map" and "filter" in absence of inlined lambdas. Update JavaScript style guide to 2.64: - Clarify rules for requiring and providing inner dependencies on classes. - Clarify semicolons for functions. - Note proper namespace and filename casing. - Fix typos: "@extends." - Permit parentheses to be omitted on unions. - Don't require method descriptions when obvious. - "in" is a keyword, put it in <code>. - New "Aliasing with goog.scope" section. - Rewrite the "Constants" section. - Remove the recommendation to use join() to build strings. - Add the "@expose" annotation. - Fix the "@suppress" example. - Remove reference alternate cast syntax. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - Say that "use strict" is not required. - Fix links to "optional" section. - Rewrite "JavaScript Types" section. - Fix typos: "parameterizes," "converted." - Prefer in-constructor field initialization. - Add a section on "delete" and null-assignment. - Add a note about optional JSDoc comments on enum values. - State explicitly that dot operators belong at the ends of lines. - Add "@dict" and "@struct" annotations. - Add links to the JavaScript Types section. - Require (rather than encourage) compiling. Update HTML/CSS style guide to 2.19: - Rephrased quotation guidelines. - Updated W3C I18N article reference. - Fixed revision number. Update styleguide.xsl to 1.34: - Fix error in RefreshVisibilityFromHashParam when a URL fragment points to a named anchor within a section, as used by the JavaScript style guide.
2012-11-29 04:26:27 +08:00
really catch everything including misspelled names, sys.exit()
calls, Ctrl+C interrupts, unittest failures and all kinds of
other exceptions that you simply don't want to catch.</li>
A pyguide.html
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<li>Minimize the amount of code in a
<code>try</code>/<code>except</code> block. The larger the
body of the <code>try</code>, the more likely that an
exception will be raised by a line of code that you didn't
expect to raise an exception. In those cases,
the <code>try</code>/<code>except</code> block hides a real
error.</li>
<li>Use the <code>finally</code> clause to execute code whether
or not an exception is raised in the <code>try</code> block.
This is often useful for cleanup, i.e., closing a file.</li>
Updating python style guide
2012-09-19 07:16:02 +08:00
<li>When capturing an exception, use <code>as</code> rather than
a comma. For example:
<DIV class=""><PRE>
<span class="external"></span>try:
<span class="external"> </span>raise Error
<span class="external"></span>except Error as error:
<span class="external"> </span>pass</PRE></DIV>
</li>
A pyguide.html
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</ul>
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Global_variables" id="Global_variables">Global variables</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Global_variables__button" name="link-Global_variables__button"><A href="?showone=Global_variables#Global_variables">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Global_variables')" name="Global_variables__button" id="Global_variables__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Avoid global variables.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Global_variables__body" id="Global_variables__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
Variables that are declared at the module level.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Occasionally useful.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
Has the potential to change module behavior during the import,
because assignments to module-level variables are done when the
module is imported.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Avoid global variables in favor of class variables. Some
exceptions are:
<ul>
<li>Default options for scripts.</li>
<li>Module-level constants. For example: <code>PI = 3.14159</code>.
Constants should be named using all caps with underscores;
see <a HREF="#Naming">Naming</a> below.</li>
<li>It is sometimes useful for globals to cache values needed
or returned by functions.</li>
<li>If needed, globals should be made internal to the module
and accessed through public module level functions;
see <a HREF="#Naming">Naming</a> below.</li>
</ul>
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Nested/Local/Inner_Classes_and_Functions" id="Nested/Local/Inner_Classes_and_Functions">Nested/Local/Inner Classes and Functions</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Nested/Local/Inner_Classes_and_Functions__button" name="link-Nested/Local/Inner_Classes_and_Functions__button"><A href="?showone=Nested/Local/Inner_Classes_and_Functions#Nested/Local/Inner_Classes_and_Functions">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Nested/Local/Inner_Classes_and_Functions')" name="Nested/Local/Inner_Classes_and_Functions__button" id="Nested/Local/Inner_Classes_and_Functions__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Nested/local/inner classes and functions are fine.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Nested/Local/Inner_Classes_and_Functions__body" id="Nested/Local/Inner_Classes_and_Functions__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
Update C++ style guide to 3.146: - Make the messaging on DISALLOW_EVIL_CONSTRUCTORS more clear that we should not be rewriting old code but should simply prefer DISALLOW_COPY_AND_ASSIGN on new code. - s/Initializer Lists/Constructor Initializer Lists/ since people search for this based on knowing it's part of the constructor, but forget the precise name. - Allow data members in a test fixture to be private. - Loosen restrictions on globals. - Add explicit guideline for nested namespace formatting. - Strengthen the prohibition against operator overloading for operator&. - Add recommendation for "_" over "-" in file names. - Revise the "Copy Constructors" section for brevity and clarity. Emphasize preference for standard over nonstandard copy operations. - Weaken the wording at the top of the "Doing Work in Constructors" section, making it clear that Init() methods are not absolutely required for non-trivial initialization. - Fix minor typos and grammatical errors. Update Objective-C style guide to 2.14: - Add the Rule of Four for indenting parameters. Allow either of two forms for formatting methods with short first keywords. - Update the guidance on BOOL vs. bool. - Whitespace cleanup. Update Python style guide to 2.14: - Consolidate discussion of the string module, apply, map, filter, and reduce into a single section. - Make it explicit that functions and classes can be nested inside methods.
2009-10-24 05:01:49 +08:00
A class can be defined inside of a method, function, or class. A
function can be defined inside a method or function. Nested functions
have read-only access to variables defined in enclosing scopes.
A pyguide.html
2009-07-24 04:09:56 +08:00
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Allows definition of utility classes and functions that are only
used inside of a very limited scope. Very <a HREF="http://en.wikipedia.org/wiki/Abstract_data_type">ADT</a>-y.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
Instances of nested or local classes cannot be pickled.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
They are fine.
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="List_Comprehensions" id="List_Comprehensions">List Comprehensions</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-List_Comprehensions__button" name="link-List_Comprehensions__button"><A href="?showone=List_Comprehensions#List_Comprehensions">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('List_Comprehensions')" name="List_Comprehensions__button" id="List_Comprehensions__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Okay to use for simple cases.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="List_Comprehensions__body" id="List_Comprehensions__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
List comprehensions and generator expressions provide a concise
and efficient way to create lists and iterators without
resorting to the use of <code>map()</code>,
<code>filter()</code>, or <code>lambda</code>.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Simple list comprehensions can be clearer and simpler than
other list creation techniques. Generator expressions can be
very efficient, since they avoid the creation of a list
entirely.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
Complicated list comprehensions or generator expressions can be
hard to read.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Okay to use for simple cases. Each portion must fit on one line:
mapping expression, <code>for</code> clause, filter expression.
Multiple <code>for</code> clauses or filter expressions are not
permitted. Use loops instead when things get more complicated.
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Ye<span class="external"></span>s:
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>result = []
<span class="external"></span>for x in range(10):
<span class="external"> </span>for y in range(5):
<span class="external"> </span>if x * y &gt; 10:
<span class="external"> </span>result.append((x, y))
<span class="external"></span>for x in xrange(5):
<span class="external"> </span>for y in xrange(5):
<span class="external"> </span>if x != y:
<span class="external"> </span>for z in xrange(5):
<span class="external"> </span>if y != z:
<span class="external"> </span>yield (x, y, z)
<span class="external"></span>return ((x, complicated_transform(x))
<span class="external"></span> for x in long_generator_function(parameter)
<span class="external"></span> if x is not None)
<span class="external"></span>squares = [x * x for x in range(10)]
<span class="external"></span>eat(jelly_bean for jelly_bean in jelly_beans
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span> if jelly_bean.color == 'black')</PRE></DIV>
Updating python style guide
2012-09-19 07:16:02 +08:00
<DIV class=""><PRE class="badcode">No<span class="external"></span>:
<span class="external"></span>result = [(x, y) for x in range(10) for y in range(5) if x * y &gt; 10]
<span class="external"></span>return ((x, y, z)
<span class="external"></span> for x in xrange(5)
<span class="external"></span> for y in xrange(5)
<span class="external"></span> if x != y
<span class="external"></span> for z in xrange(5)
<span class="external"></span> if y != z)</PRE></DIV>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Default_Iterators_and_Operators" id="Default_Iterators_and_Operators">Default Iterators and Operators</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Default_Iterators_and_Operators__button" name="link-Default_Iterators_and_Operators__button"><A href="?showone=Default_Iterators_and_Operators#Default_Iterators_and_Operators">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Default_Iterators_and_Operators')" name="Default_Iterators_and_Operators__button" id="Default_Iterators_and_Operators__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
Use default iterators and operators for types that support them,
A pyguide.html
2009-07-24 04:09:56 +08:00
like lists, dictionaries, and files.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Default_Iterators_and_Operators__body" id="Default_Iterators_and_Operators__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
Container types, like dictionaries and lists, define default
iterators and membership test operators ("in" and "not in").
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
The default iterators and operators are simple and efficient.
They express the operation directly, without extra method calls.
A function that uses default operators is generic. It can be
used with any type that supports the operation.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
You can't tell the type of objects by reading the method names
(e.g. has_key() means a dictionary). This is also an advantage.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN> Use default iterators and operators for types
that support them, like lists, dictionaries, and files. The
built-in types define iterator methods, too. Prefer these
methods to methods that return lists, except that you should not
mutate a container while iterating over it.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>for key in adict: ...
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>if key not in adict: ...
<span class="external"></span>if obj in alist: ...
<span class="external"></span>for line in afile: ...
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>for k, v in dict.iteritems(): ...</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>for key in adict.keys(): ...
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>if not adict.has_key(key): ...
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>for line in afile.readlines(): ...</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Generators" id="Generators">Generators</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Generators__button" name="link-Generators__button"><A href="?showone=Generators#Generators">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Generators')" name="Generators__button" id="Generators__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Use generators as needed.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Generators__body" id="Generators__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
A generator function returns an iterator that yields a value each
time it executes a yield statement. After it yields a value, the
runtime state of the generator function is suspended until the
next value is needed.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Simpler code, because the state of local variables and control flow
are preserved for each call. A generator uses less memory than a
function that creates an entire list of values at once.
</P>
<P class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
<SPAN class="stylepoint_section">Cons: </SPAN>
A pyguide.html
2009-07-24 04:09:56 +08:00
None.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Fine. Use "Yields:" rather than "Returns:" in the
doc string for generator functions.
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Lambda_Functions" id="Lambda_Functions">Lambda Functions</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Lambda_Functions__button" name="link-Lambda_Functions__button"><A href="?showone=Lambda_Functions#Lambda_Functions">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Lambda_Functions')" name="Lambda_Functions__button" id="Lambda_Functions__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Okay for one-liners.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Lambda_Functions__body" id="Lambda_Functions__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
Lambdas define anonymous functions in an expression, as
opposed to a statement. They are often used to define callbacks or
operators for higher-order functions like <code>map()</code> and
<code>filter()</code>.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Convenient.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN> Harder to read and debug than local functions. The
lack of names means stack traces are more difficult to
understand. Expressiveness is limited because the function may
only contain an expression.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Okay to use them for one-liners. If the code inside the lambda
function is any longer than 60–80 chars, it's probably better to
define it as a regular (nested) function.
<p>
For common operations like multiplication, use the functions from the
<code>operator</code> module instead of lambda functions. For
example, prefer <code>operator.mul</code> to <code>lambda
x, y: x * y</code>.
</p>
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
<H3><A name="Conditional_Expressions" id="Conditional_Expressions">Conditional Expressions</A></H3>
<SPAN class="link_button" id="link-Conditional_Expressions__button" name="link-Conditional_Expressions__button"><A href="?showone=Conditional_Expressions#Conditional_Expressions">
link
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Conditional_Expressions')" name="Conditional_Expressions__button" id="Conditional_Expressions__button">▶</SPAN>
<DIV style="display:inline;" class="">
Okay for one-liners.
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Conditional_Expressions__body" id="Conditional_Expressions__body" style="display: none">
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
Conditional expressions are mechanisms that provide a shorter syntax
for if statements. For example:
<code>x = 1 if cond else 2</code>.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Shorter and more convenient than an if statement.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
May be harder to read than an if statement. The condition may be difficult
to locate if the expression is long.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Okay to use for one-liners. In other cases prefer to use a complete if
statement.
</P>
</DIV></DIV>
</DIV>
<DIV class="">
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<H3><A name="Default_Argument_Values" id="Default_Argument_Values">Default Argument Values</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Default_Argument_Values__button" name="link-Default_Argument_Values__button"><A href="?showone=Default_Argument_Values#Default_Argument_Values">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Default_Argument_Values')" name="Default_Argument_Values__button" id="Default_Argument_Values__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Okay in most cases.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Default_Argument_Values__body" id="Default_Argument_Values__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
You can specify values for variables at the end of a function's
parameter list, e.g., <code>def foo(a, b=0):</code>. If
<code>foo</code> is called with only one argument,
<code>b</code> is set to 0. If it is called with two arguments,
<code>b</code> has the value of the second argument.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Often you have a function that uses lots of default values,
but—rarely—you want to override the
defaults. Default argument values provide an easy way to do this,
without having to define lots of functions for the rare
exceptions. Also, Python does not support overloaded
methods/functions and default arguments are an easy way of
"faking" the overloading behavior.
</P>
<P class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
<SPAN class="stylepoint_section">Cons: </SPAN>
A pyguide.html
2009-07-24 04:09:56 +08:00
Default arguments are evaluated once at module load
time. This may cause problems if the argument is a mutable
object such as a list or a dictionary. If the function modifies
the object (e.g., by appending an item to a list), the default
value is modified.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Okay to use with the following caveats:
<p>
Do not use mutable objects as default values in the function or method
definition.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>def foo(a, b=None):
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>if b is None:
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"> </span>b = []</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>def foo(a, b=[]):
<span class="external"> </span>...</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Update C++ style guide to 3.146: - Make the messaging on DISALLOW_EVIL_CONSTRUCTORS more clear that we should not be rewriting old code but should simply prefer DISALLOW_COPY_AND_ASSIGN on new code. - s/Initializer Lists/Constructor Initializer Lists/ since people search for this based on knowing it's part of the constructor, but forget the precise name. - Allow data members in a test fixture to be private. - Loosen restrictions on globals. - Add explicit guideline for nested namespace formatting. - Strengthen the prohibition against operator overloading for operator&. - Add recommendation for "_" over "-" in file names. - Revise the "Copy Constructors" section for brevity and clarity. Emphasize preference for standard over nonstandard copy operations. - Weaken the wording at the top of the "Doing Work in Constructors" section, making it clear that Init() methods are not absolutely required for non-trivial initialization. - Fix minor typos and grammatical errors. Update Objective-C style guide to 2.14: - Add the Rule of Four for indenting parameters. Allow either of two forms for formatting methods with short first keywords. - Update the guidance on BOOL vs. bool. - Whitespace cleanup. Update Python style guide to 2.14: - Consolidate discussion of the string module, apply, map, filter, and reduce into a single section. - Make it explicit that functions and classes can be nested inside methods.
2009-10-24 05:01:49 +08:00
Calling code must use named values for arguments with a default value.
This helps document the code somewhat and helps prevent and detect
A pyguide.html
2009-07-24 04:09:56 +08:00
interface breakage when more arguments are added.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>def foo(a, b=1):
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"> </span>...</PRE></DIV>
<DIV class=""><PRE>Yes: <span class="external"></span>foo(1)
<span class="external"></span>foo(1, b=2)</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>foo(1, 2)</PRE></DIV>
</P>
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Properties" id="Properties">Properties</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Properties__button" name="link-Properties__button"><A href="?showone=Properties#Properties">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Properties')" name="Properties__button" id="Properties__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
Use properties for accessing or setting data where you would
normally have used simple, lightweight accessor or setter methods.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Properties__body" id="Properties__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN> A way to wrap method calls for getting and
setting an attribute as a standard attribute access when the
computation is lightweight.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN> Readability is increased by eliminating explicit
get and set method calls for simple attribute access. Allows
calculations to be lazy. Considered the Pythonic way to
maintain the interface of a class. In terms of performance,
allowing properties bypasses needing trivial accessor methods
when a direct variable access is reasonable. This also allows
accessor methods to be added in the future without breaking the
interface.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN> Properties are specified after the getter and
setter methods are declared, requiring one to notice they are
used for properties farther down in the code (except for readonly
properties created with the <code>@property</code> decorator - see
below). Must inherit from
<code>object</code>. Can hide side-effects much like operator
overloading. Can be confusing for subclasses.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN> Use properties in new code to access or
set data where you would normally have used simple, lightweight
accessor or setter methods. Read-only properties should be created
Updating python style guide
2012-09-19 07:16:02 +08:00
with the <code>@property</code>
A pyguide.html
2009-07-24 04:09:56 +08:00
<a HREF="#Function_and_Method_Decorators">decorator</a>.
<p><a id="properties-template-dp">
Inheritance with properties can be non-obvious if the property itself is
not overridden. Thus one must make sure that accessor methods are
called indirectly to ensure methods overridden in subclasses are called
by the property (using the Template Method DP).
</a></p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>import math
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>class Square(object):
<span class="external"> </span>"""A square with two properties: a writable area and a read-only perimeter.
<span class="external"> </span>To use:
<span class="external"> </span>&gt;&gt;&gt; sq = Square(3)
<span class="external"> </span>&gt;&gt;&gt; sq.area
<span class="external"> </span>9
<span class="external"> </span>&gt;&gt;&gt; sq.perimeter
<span class="external"> </span>12
<span class="external"> </span>&gt;&gt;&gt; sq.area = 16
<span class="external"> </span>&gt;&gt;&gt; sq.side
<span class="external"> </span>4
<span class="external"> </span>&gt;&gt;&gt; sq.perimeter
<span class="external"> </span>16
<span class="external"> </span>"""
<span class="external"> </span>def __init__(self, side):
<span class="external"> </span>self.side = side
<span class="external"> </span>def __get_area(self):
<span class="external"> </span>"""Calculates the 'area' property."""
<span class="external"> </span>return self.side ** 2
<span class="external"> </span>def ___get_area(self):
<span class="external"> </span>"""Indirect accessor for 'area' property."""
<span class="external"> </span>return self.__get_area()
<span class="external"> </span>def __set_area(self, area):
<span class="external"> </span>"""Sets the 'area' property."""
<span class="external"> </span>self.side = math.sqrt(area)
<span class="external"> </span>def ___set_area(self, area):
<span class="external"> </span>"""Indirect setter for 'area' property."""
Update JavaScript style guide to 2.28: - Fix typo. Update Python style guide to 2.29: - Fix indirect setter.
2011-11-05 05:13:33 +08:00
<span class="external"> </span>self.__set_area(area)
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>area = property(___get_area, ___set_area,
<span class="external"> </span> doc="""Gets or sets the area of the square.""")
<span class="external"> </span>@property
<span class="external"> </span>def perimeter(self):
<span class="external"> </span>return self.side * 4
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="True/False_evaluations" id="True/False_evaluations">True/False evaluations</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-True/False_evaluations__button" name="link-True/False_evaluations__button"><A href="?showone=True/False_evaluations#True/False_evaluations">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('True/False_evaluations')" name="True/False_evaluations__button" id="True/False_evaluations__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Use the "implicit" false if at all possible.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="True/False_evaluations__body" id="True/False_evaluations__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN> Python evaluates certain values as <code>false</code>
when in a boolean context. A quick "rule of thumb" is that all
"empty" values are considered <code>false</code> so <code>0, None, [], {},
Updating python style guide
2012-09-19 07:16:02 +08:00
''</code> all evaluate as <code>false</code> in a boolean context.
A pyguide.html
2009-07-24 04:09:56 +08:00
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN> Conditions using Python booleans are easier to read
and less error-prone. In most cases, they're also faster.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
May look strange to C/C++ developers.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Use the "implicit" false if at all possible, e.g., <code>if
foo:</code> rather than <code>if foo != []:</code>. There are a
few caveats that you should keep in mind though:
<ul>
<li>
Never use <code>==</code> or <code>!=</code> to compare
singletons like <code>None</code>. Use <code>is</code>
or <code>is not</code>.</li>
<li>Beware of writing <code>if x:</code> when you really mean
<code>if x is not None:</code>—e.g., when testing whether
a variable or argument that defaults to <code>None</code> was
set to some other value. The other value might be a value
that's false in a boolean context!</li>
<li>
Never compare a boolean variable to <code>False</code> using
<code>==</code>. Use <code>if not x:</code> instead. If
you need to distinguish <code>False</code> from
<code>None</code> then chain the expressions,
such as <code>if not x and x is not None:</code>.
</li>
<li>
For sequences (strings, lists, tuples), use the fact that
empty sequences are false, so <code>if not seq:</code> or
<code>if seq:</code> is preferable to <code>if
len(seq):</code> or <code>if not
len(seq):</code>.</li>
<li>
When handling integers, implicit false may involve more risk than
benefit (i.e., accidentally handling <code>None</code> as 0). You may
compare a value which is known to be an integer (and is not the
result of <code>len()</code>) against the integer 0.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>if not users:
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>print 'no users'
<span class="external"></span>if foo == 0:
<span class="external"> </span>self.handle_zero()
<span class="external"></span>if i % 10 == 0:
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"> </span>self.handle_multiple_of_ten()</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>if len(users) == 0:
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>print 'no users'
<span class="external"></span>if foo is not None and not foo:
<span class="external"> </span>self.handle_zero()
<span class="external"></span>if not i % 10:
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"> </span>self.handle_multiple_of_ten()</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
</li>
<li>
Note that <code>'0'</code> (i.e., <code>0</code> as string)
evaluates to true.</li>
</ul>
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Deprecated_Language_Features" id="Deprecated_Language_Features">Deprecated Language Features</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Deprecated_Language_Features__button" name="link-Deprecated_Language_Features__button"><A href="?showone=Deprecated_Language_Features#Deprecated_Language_Features">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Deprecated_Language_Features')" name="Deprecated_Language_Features__button" id="Deprecated_Language_Features__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Update C++ style guide to 3.146: - Make the messaging on DISALLOW_EVIL_CONSTRUCTORS more clear that we should not be rewriting old code but should simply prefer DISALLOW_COPY_AND_ASSIGN on new code. - s/Initializer Lists/Constructor Initializer Lists/ since people search for this based on knowing it's part of the constructor, but forget the precise name. - Allow data members in a test fixture to be private. - Loosen restrictions on globals. - Add explicit guideline for nested namespace formatting. - Strengthen the prohibition against operator overloading for operator&. - Add recommendation for "_" over "-" in file names. - Revise the "Copy Constructors" section for brevity and clarity. Emphasize preference for standard over nonstandard copy operations. - Weaken the wording at the top of the "Doing Work in Constructors" section, making it clear that Init() methods are not absolutely required for non-trivial initialization. - Fix minor typos and grammatical errors. Update Objective-C style guide to 2.14: - Add the Rule of Four for indenting parameters. Allow either of two forms for formatting methods with short first keywords. - Update the guidance on BOOL vs. bool. - Whitespace cleanup. Update Python style guide to 2.14: - Consolidate discussion of the string module, apply, map, filter, and reduce into a single section. - Make it explicit that functions and classes can be nested inside methods.
2009-10-24 05:01:49 +08:00
Use string methods instead of the <code>string</code> module
where possible. Use function call syntax instead
of <code>apply</code>. Use list comprehensions
Update C++ style guide to 3.231: - Clarify that sentence-like non-sentence comments are permitted. - Note that older code with incorrect #include ordering should be fixed. - Revamp the section on default function arguments. - Avoid explicitly recommending Init() methods. - C++11: permit "auto". - C++11: permit ">>" in place of "> >". - C++11: permit range-based "for". - C++11: permit variadic macros (already permitted as a C++03 extension). - C++11: permit "LL" and "ULL" literal suffixes (already permitted as a C++03 extension). - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - C++11: permit new features in <algorithm> and the portion of <numeric> that does not require initializer lists. - Revise rules on forward declarations: explicitly forbid forward-declared functions, do not mandate forward declarations, discourage forward-declared templates. - Remove the rule requiring "const" qualifiers for member functions to be on the same line as the closing parenthesis of the parameter list. - Fix typo: "unnamed namespaces." - C++11: permit local types as template parameters. - Fix typo: "unfamiliar." - Relax RTTI rules to permit its use, but warn about its abuse. - C++11: permit nullptr and nullptr_t. Revise text referring to NULL to refer more generically to null pointers. - Remove the "don't go crazy with const" rule. - Fix typo: "dir/foo2" should bee "dir2/foo2." - Remove reference to a specific GCC version. Update Objective-C style guide to 2.48: - Revise method declaration and invocation formatting rules for long names. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. Top-of-file comments are not required. - Fix dead link in the "nil Checks" section. - Cover ARC. - Specify that @private is only required for instance variables in header files. - Permit NSNumber literals. - Change the naming convention for instance variables from trailing underscore to leading underscore, allowing a wide exception for existing code and projects. - Fix description of BOOL with respect to its signedness. Update Python style guide to 2.45: - Recommend "pylint: disable" over "pylint: disable-msg." - Fix case-sensitive anchor. - Provide a better explanation of the problems with catch-all "except:." - Permit "map" and "filter" in absence of inlined lambdas. Update JavaScript style guide to 2.64: - Clarify rules for requiring and providing inner dependencies on classes. - Clarify semicolons for functions. - Note proper namespace and filename casing. - Fix typos: "@extends." - Permit parentheses to be omitted on unions. - Don't require method descriptions when obvious. - "in" is a keyword, put it in <code>. - New "Aliasing with goog.scope" section. - Rewrite the "Constants" section. - Remove the recommendation to use join() to build strings. - Add the "@expose" annotation. - Fix the "@suppress" example. - Remove reference alternate cast syntax. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - Say that "use strict" is not required. - Fix links to "optional" section. - Rewrite "JavaScript Types" section. - Fix typos: "parameterizes," "converted." - Prefer in-constructor field initialization. - Add a section on "delete" and null-assignment. - Add a note about optional JSDoc comments on enum values. - State explicitly that dot operators belong at the ends of lines. - Add "@dict" and "@struct" annotations. - Add links to the JavaScript Types section. - Require (rather than encourage) compiling. Update HTML/CSS style guide to 2.19: - Rephrased quotation guidelines. - Updated W3C I18N article reference. - Fixed revision number. Update styleguide.xsl to 1.34: - Fix error in RefreshVisibilityFromHashParam when a URL fragment points to a named anchor within a section, as used by the JavaScript style guide.
2012-11-29 04:26:27 +08:00
and <code>for</code> loops instead of <code>filter</code> and
<code>map</code> when the function argument would have been an
inlined lambda anyway. Use <code>for</code> loops instead of
<code>reduce</code>.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Deprecated_Language_Features__body" id="Deprecated_Language_Features__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<P class="">
Update C++ style guide to 3.146: - Make the messaging on DISALLOW_EVIL_CONSTRUCTORS more clear that we should not be rewriting old code but should simply prefer DISALLOW_COPY_AND_ASSIGN on new code. - s/Initializer Lists/Constructor Initializer Lists/ since people search for this based on knowing it's part of the constructor, but forget the precise name. - Allow data members in a test fixture to be private. - Loosen restrictions on globals. - Add explicit guideline for nested namespace formatting. - Strengthen the prohibition against operator overloading for operator&. - Add recommendation for "_" over "-" in file names. - Revise the "Copy Constructors" section for brevity and clarity. Emphasize preference for standard over nonstandard copy operations. - Weaken the wording at the top of the "Doing Work in Constructors" section, making it clear that Init() methods are not absolutely required for non-trivial initialization. - Fix minor typos and grammatical errors. Update Objective-C style guide to 2.14: - Add the Rule of Four for indenting parameters. Allow either of two forms for formatting methods with short first keywords. - Update the guidance on BOOL vs. bool. - Whitespace cleanup. Update Python style guide to 2.14: - Consolidate discussion of the string module, apply, map, filter, and reduce into a single section. - Make it explicit that functions and classes can be nested inside methods.
2009-10-24 05:01:49 +08:00
<SPAN class="stylepoint_section">Definition: </SPAN>
Current versions of Python provide alternative constructs
that people find generally preferable.
A pyguide.html
2009-07-24 04:09:56 +08:00
</P>
<P class="">
Update C++ style guide to 3.146: - Make the messaging on DISALLOW_EVIL_CONSTRUCTORS more clear that we should not be rewriting old code but should simply prefer DISALLOW_COPY_AND_ASSIGN on new code. - s/Initializer Lists/Constructor Initializer Lists/ since people search for this based on knowing it's part of the constructor, but forget the precise name. - Allow data members in a test fixture to be private. - Loosen restrictions on globals. - Add explicit guideline for nested namespace formatting. - Strengthen the prohibition against operator overloading for operator&. - Add recommendation for "_" over "-" in file names. - Revise the "Copy Constructors" section for brevity and clarity. Emphasize preference for standard over nonstandard copy operations. - Weaken the wording at the top of the "Doing Work in Constructors" section, making it clear that Init() methods are not absolutely required for non-trivial initialization. - Fix minor typos and grammatical errors. Update Objective-C style guide to 2.14: - Add the Rule of Four for indenting parameters. Allow either of two forms for formatting methods with short first keywords. - Update the guidance on BOOL vs. bool. - Whitespace cleanup. Update Python style guide to 2.14: - Consolidate discussion of the string module, apply, map, filter, and reduce into a single section. - Make it explicit that functions and classes can be nested inside methods.
2009-10-24 05:01:49 +08:00
<SPAN class="stylepoint_section">Decision: </SPAN>
We do not use any Python version which does not support
these features, so there is no reason not to use the new
styles.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>words = foo.split(':')
Update C++ style guide to 3.146: - Make the messaging on DISALLOW_EVIL_CONSTRUCTORS more clear that we should not be rewriting old code but should simply prefer DISALLOW_COPY_AND_ASSIGN on new code. - s/Initializer Lists/Constructor Initializer Lists/ since people search for this based on knowing it's part of the constructor, but forget the precise name. - Allow data members in a test fixture to be private. - Loosen restrictions on globals. - Add explicit guideline for nested namespace formatting. - Strengthen the prohibition against operator overloading for operator&. - Add recommendation for "_" over "-" in file names. - Revise the "Copy Constructors" section for brevity and clarity. Emphasize preference for standard over nonstandard copy operations. - Weaken the wording at the top of the "Doing Work in Constructors" section, making it clear that Init() methods are not absolutely required for non-trivial initialization. - Fix minor typos and grammatical errors. Update Objective-C style guide to 2.14: - Add the Rule of Four for indenting parameters. Allow either of two forms for formatting methods with short first keywords. - Update the guidance on BOOL vs. bool. - Whitespace cleanup. Update Python style guide to 2.14: - Consolidate discussion of the string module, apply, map, filter, and reduce into a single section. - Make it explicit that functions and classes can be nested inside methods.
2009-10-24 05:01:49 +08:00
<span class="external"></span>[x[1] for x in my_list if x[2] == 5]
Update C++ style guide to 3.231: - Clarify that sentence-like non-sentence comments are permitted. - Note that older code with incorrect #include ordering should be fixed. - Revamp the section on default function arguments. - Avoid explicitly recommending Init() methods. - C++11: permit "auto". - C++11: permit ">>" in place of "> >". - C++11: permit range-based "for". - C++11: permit variadic macros (already permitted as a C++03 extension). - C++11: permit "LL" and "ULL" literal suffixes (already permitted as a C++03 extension). - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - C++11: permit new features in <algorithm> and the portion of <numeric> that does not require initializer lists. - Revise rules on forward declarations: explicitly forbid forward-declared functions, do not mandate forward declarations, discourage forward-declared templates. - Remove the rule requiring "const" qualifiers for member functions to be on the same line as the closing parenthesis of the parameter list. - Fix typo: "unnamed namespaces." - C++11: permit local types as template parameters. - Fix typo: "unfamiliar." - Relax RTTI rules to permit its use, but warn about its abuse. - C++11: permit nullptr and nullptr_t. Revise text referring to NULL to refer more generically to null pointers. - Remove the "don't go crazy with const" rule. - Fix typo: "dir/foo2" should bee "dir2/foo2." - Remove reference to a specific GCC version. Update Objective-C style guide to 2.48: - Revise method declaration and invocation formatting rules for long names. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. Top-of-file comments are not required. - Fix dead link in the "nil Checks" section. - Cover ARC. - Specify that @private is only required for instance variables in header files. - Permit NSNumber literals. - Change the naming convention for instance variables from trailing underscore to leading underscore, allowing a wide exception for existing code and projects. - Fix description of BOOL with respect to its signedness. Update Python style guide to 2.45: - Recommend "pylint: disable" over "pylint: disable-msg." - Fix case-sensitive anchor. - Provide a better explanation of the problems with catch-all "except:." - Permit "map" and "filter" in absence of inlined lambdas. Update JavaScript style guide to 2.64: - Clarify rules for requiring and providing inner dependencies on classes. - Clarify semicolons for functions. - Note proper namespace and filename casing. - Fix typos: "@extends." - Permit parentheses to be omitted on unions. - Don't require method descriptions when obvious. - "in" is a keyword, put it in <code>. - New "Aliasing with goog.scope" section. - Rewrite the "Constants" section. - Remove the recommendation to use join() to build strings. - Add the "@expose" annotation. - Fix the "@suppress" example. - Remove reference alternate cast syntax. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - Say that "use strict" is not required. - Fix links to "optional" section. - Rewrite "JavaScript Types" section. - Fix typos: "parameterizes," "converted." - Prefer in-constructor field initialization. - Add a section on "delete" and null-assignment. - Add a note about optional JSDoc comments on enum values. - State explicitly that dot operators belong at the ends of lines. - Add "@dict" and "@struct" annotations. - Add links to the JavaScript Types section. - Require (rather than encourage) compiling. Update HTML/CSS style guide to 2.19: - Rephrased quotation guidelines. - Updated W3C I18N article reference. - Fixed revision number. Update styleguide.xsl to 1.34: - Fix error in RefreshVisibilityFromHashParam when a URL fragment points to a named anchor within a section, as used by the JavaScript style guide.
2012-11-29 04:26:27 +08:00
<span class="external"></span>map(math.sqrt, data) # Ok. No inlined lambda expression.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>fn(*args, **kwargs)</PRE></DIV>
Updating python style guide
2012-09-19 07:16:02 +08:00
<DIV class=""><PRE class="badcode">No: <span class="external"></span>words = string.split(foo, ':')
<span class="external"></span>map(lambda x: x[1], filter(lambda x: x[2] == 5, my_list))
<span class="external"></span>apply(fn, args, kwargs)</PRE></DIV>
A pyguide.html
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</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Lexical_Scoping" id="Lexical_Scoping">Lexical Scoping</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Lexical_Scoping__button" name="link-Lexical_Scoping__button"><A href="?showone=Lexical_Scoping#Lexical_Scoping">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Lexical_Scoping')" name="Lexical_Scoping__button" id="Lexical_Scoping__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Okay to use.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Lexical_Scoping__body" id="Lexical_Scoping__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
A nested Python function can refer to variables defined in
enclosing functions, but can not assign to them. Variable
bindings are resolved using lexical scoping, that is, based on
the static program text. Any assignment to a name in a block
will cause Python to treat all references to that name as a
local variable, even if the use precedes the assignment. If a
global declaration occurs, the name is treated as a global
variable.
Updating python style guide
2012-09-19 07:16:02 +08:00
A pyguide.html
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<p>
An example of the use of this feature is:
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>def get_adder(summand1):
<span class="external"> </span>"""Returns a function that adds numbers to a given number."""
<span class="external"> </span>def adder(summand2):
<span class="external"> </span>return summand1 + summand2
<span class="external"> </span>return adder
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
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</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN>
Often results in clearer, more elegant code. Especially comforting
to experienced Lisp and Scheme (and Haskell and ML and …)
programmers.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN>
Updating python style guide
2012-09-19 07:16:02 +08:00
Can lead to confusing bugs. Such as this example based on
A pyguide.html
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<a HREF="http://www.python.org/dev/peps/pep-0227/">PEP-0227</a>:
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE class="badcode">
A pyguide.html
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<span class="external"></span>i = 4
<span class="external"></span>def foo(x):
<span class="external"> </span>def bar():
<span class="external"> </span>print i,
<span class="external"> </span># ...
<span class="external"> </span># A bunch of code here
<span class="external"> </span># ...
<span class="external"> </span>for i in x: # Ah, i *is* local to Foo, so this is what Bar sees
<span class="external"> </span>print i,
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"> </span>bar()</PRE></DIV>
A pyguide.html
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<p>
So <code>foo([1, 2, 3])</code> will print <code>1 2 3 3</code>, not
<code>1 2 3 4</code>.
Updating python style guide
2012-09-19 07:16:02 +08:00
</p>
A pyguide.html
2009-07-24 04:09:56 +08:00
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN>
Okay to use.
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Function_and_Method_Decorators" id="Function_and_Method_Decorators">Function and Method Decorators</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Function_and_Method_Decorators__button" name="link-Function_and_Method_Decorators__button"><A href="?showone=Function_and_Method_Decorators#Function_and_Method_Decorators">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Function_and_Method_Decorators')" name="Function_and_Method_Decorators__button" id="Function_and_Method_Decorators__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Use decorators judiciously when there is a clear advantage.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Function_and_Method_Decorators__body" id="Function_and_Method_Decorators__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN>
<a HREF="http://www.python.org/doc/2.4.3/whatsnew/node6.html">Decorators
for Functions and Methods</a>
(a.k.a "the <code>@</code> notation").
The most common decorators are <code>@classmethod</code> and
<code>@staticmethod</code>, for converting ordinary methods to class or
static methods. However, the decorator syntax allows for
user-defined decorators as well. Specifically, for some function
<code>my_decorator</code>, this:
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>class C(object):
<span class="external"> </span>@my_decorator
<span class="external"> </span>def method(self):
<span class="external"> </span># method body ...
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
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is equivalent to:
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>class C(object):
<span class="external"> </span>def method(self):
<span class="external"> </span># method body ...
<span class="external"> </span>method = my_decorator(method)
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
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</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN> Elegantly specifies some transformation on a method; the
transformation might eliminate some repetitive code, enforce invariants,
etc.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN> Decorators can perform arbitrary operations on a
function's arguments or return values, resulting in surprising
implicit behavior.
Additionally, decorators execute at import time. Failures in decorator
code are pretty much impossible to recover from.
</P>
<P class="">
<SPAN class="stylepoint_section">Decision: </SPAN> Use decorators judiciously when there is a clear
advantage. Decorators should follow the same import and naming
guidelines as functions. Decorator pydoc should clearly state that the
function is a decorator. Write unit tests for decorators.
<p>
Avoid external dependencies in the decorator itself (e.g. don't rely on
files, sockets, database connections, etc.), since they might not be
available when the decorator runs (at import time, perhaps from
<code>pychecker</code> or other tools). A decorator that is
called with valid parameters should (as much as possible) be guaranteed
to succeed in all cases.
</p>
<p>
Decorators are a special case of "top level code" - see
<a HREF="#Main">main</a> for more discussion.
</p>
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Threading" id="Threading">Threading</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Threading__button" name="link-Threading__button"><A href="?showone=Threading#Threading">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Threading')" name="Threading__button" id="Threading__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Do not rely on the atomicity of built-in types.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Threading__body" id="Threading__body" style="display: none">
A pyguide.html
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<p>
While Python's built-in data types such as dictionaries appear
to have atomic operations, there are corner cases where they
aren't atomic (e.g. if <code>__hash__</code> or
<code>__eq__</code> are implemented as Python methods) and their
atomicity should not be relied upon. Neither should you rely on
atomic variable assignment (since this in turn depends on
dictionaries).
</p>
<p>
Updating python style guide
2012-09-19 07:16:02 +08:00
Use the Queue module's <code>Queue</code> data type as the preferred
A pyguide.html
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way to
communicate data between threads. Otherwise, use the threading
module and its locking primitives. Learn about the proper use
of condition variables so you can use
<code>threading.Condition</code> instead of using lower-level
locks.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Power_Features" id="Power_Features">Power Features</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Power_Features__button" name="link-Power_Features__button"><A href="?showone=Power_Features#Power_Features">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Power_Features')" name="Power_Features__button" id="Power_Features__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Avoid these features.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Power_Features__body" id="Power_Features__body" style="display: none">
A pyguide.html
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<P class="">
<SPAN class="stylepoint_section">Definition: </SPAN> Python is an extremely flexible language and
gives you many fancy features such as metaclasses, access to bytecode,
on-the-fly compilation, dynamic inheritance, object reparenting,
import hacks, reflection, modification of system internals,
etc.
</P>
<P class="">
<SPAN class="stylepoint_section">Pros: </SPAN> These are powerful language features. They can
make your code more compact.
</P>
<P class="">
<SPAN class="stylepoint_section">Cons: </SPAN> It's very tempting to use these "cool" features
when they're not absolutely necessary. It's harder to read,
understand, and debug code that's using unusual features
underneath. It doesn't seem that way at first (to the original
author), but when revisiting the code, it tends to be more
difficult than code that is longer but is straightforward.
</P>
<P class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
<SPAN class="stylepoint_section">Decision: </SPAN>
A pyguide.html
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Avoid these features in
your code.
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
</DIV>
<DIV class="">
<H2 name="Python_Style_Rules" id="Python_Style_Rules">Python Style Rules</H2>
<DIV class="">
<H3><A name="Semicolons" id="Semicolons">Semicolons</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Semicolons__button" name="link-Semicolons__button"><A href="?showone=Semicolons#Semicolons">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Semicolons')" name="Semicolons__button" id="Semicolons__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Do not terminate your lines with semi-colons and do not use
semi-colons to put two commands on the same line.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Semicolons__body" id="Semicolons__body" style="display: none">
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Line_length" id="Line_length">Line length</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Line_length__button" name="link-Line_length__button"><A href="?showone=Line_length#Line_length">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Line_length')" name="Line_length__button" id="Line_length__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Maximum line length is <em>80 characters</em>.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Line_length__body" id="Line_length__body" style="display: none">
A pyguide.html
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<p>
Update C++ style guide to 3.245: - Relax the rule for sizeof(varname) vs. sizeof(type). - Allow an exception for nonconst reference parameters where convention dictates their use, such as for swap. - C++11: allow static_assert. - Require non-trivial fall-through between cases in switch statements to be annotated. Trivial fall-through includes consecutive case labels with no intervening code, and no comment is required in these cases. - C++11: allow constexpr. - Revise the "Integer Types" section to note type-width problems. - Clarify that the "arguments on subsequent lines" function call style is acceptable even when the 80-column limit doesn't require it. - Boost: allow part of Polygon. - C++11: allow <tuple>. Update Objective-C style guide to 2.52: - Fix ARC example to not imply the use of @private in .m files. - Add an example to the "Category Names" section. - Require that ARC-using files insert preprocessor directives that generate an error when compiling without ARC. - Fix spacing around the *s in the ARC example per the C++ style guide. Update Python style guide to 2.48: - Allow comments with URLs to exceed 80 characters per line. - Update outdated implicit-line-joining URLs. Update HTML/CSS style guide to 2.21: - Consistent use of title case. - Add new "Declaration Block Separation" section. - Add a CSS example to the "Capitalization" section. - Minor fixes to whitespace. Update JavaScript style to guide to 2.72: - Make it clear that the injunction against aliasing namespaces only applies to local aliases, not goog.scope. - Clarify the style guide's recommendation on array/object literals. - Add documentation on @private {type}, @protected {type}, and @const {type}. - Make JSDoc descriptions required only if not obvious. - Clarify that only private properties and methods need a trailing underscore. - Fix spelling of arv's name. Update Common Lisp style guide to 1.18: - Macro-defining macros are harder to understand for everyone, not just for the "uninitiated." There's no need to condescend. In all of the above style guides: - The guide source is now encoded as UTF-8. The numeric character references have been replaced with raw UTF-8-encoded characters.
2013-03-22 00:03:26 +08:00
Exceptions:
<ul>
<li>Long import statements.</li>
<li>URLs in comments.</li>
</ul>
A pyguide.html
2009-07-24 04:09:56 +08:00
</p>
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
<p>
Do not use backslash line continuation.
</p>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Make use of Python's
Update C++ style guide to 3.245: - Relax the rule for sizeof(varname) vs. sizeof(type). - Allow an exception for nonconst reference parameters where convention dictates their use, such as for swap. - C++11: allow static_assert. - Require non-trivial fall-through between cases in switch statements to be annotated. Trivial fall-through includes consecutive case labels with no intervening code, and no comment is required in these cases. - C++11: allow constexpr. - Revise the "Integer Types" section to note type-width problems. - Clarify that the "arguments on subsequent lines" function call style is acceptable even when the 80-column limit doesn't require it. - Boost: allow part of Polygon. - C++11: allow <tuple>. Update Objective-C style guide to 2.52: - Fix ARC example to not imply the use of @private in .m files. - Add an example to the "Category Names" section. - Require that ARC-using files insert preprocessor directives that generate an error when compiling without ARC. - Fix spacing around the *s in the ARC example per the C++ style guide. Update Python style guide to 2.48: - Allow comments with URLs to exceed 80 characters per line. - Update outdated implicit-line-joining URLs. Update HTML/CSS style guide to 2.21: - Consistent use of title case. - Add new "Declaration Block Separation" section. - Add a CSS example to the "Capitalization" section. - Minor fixes to whitespace. Update JavaScript style to guide to 2.72: - Make it clear that the injunction against aliasing namespaces only applies to local aliases, not goog.scope. - Clarify the style guide's recommendation on array/object literals. - Add documentation on @private {type}, @protected {type}, and @const {type}. - Make JSDoc descriptions required only if not obvious. - Clarify that only private properties and methods need a trailing underscore. - Fix spelling of arv's name. Update Common Lisp style guide to 1.18: - Macro-defining macros are harder to understand for everyone, not just for the "uninitiated." There's no need to condescend. In all of the above style guides: - The guide source is now encoded as UTF-8. The numeric character references have been replaced with raw UTF-8-encoded characters.
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<a HREF="http://docs.python.org/reference/lexical_analysis.html#implicit-line-joining">implicit
A pyguide.html
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line joining inside parentheses, brackets and braces</a>.
If necessary, you can add an extra pair of parentheses around an
expression.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE>Yes: foo_bar(self, width, height, color='black', design=None, x='foo',
A pyguide.html
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emphasis=None, highlight=0)
if (width == 0 and height == 0 and
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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color == 'red' and emphasis == 'strong'):</PRE></DIV>
A pyguide.html
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<p>
When a literal string won't fit on a single line, use parentheses for
implicit line joining.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>x = ('This will build a very long long '
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span> 'long long long long long long string')</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
Update C++ style guide to 3.245: - Relax the rule for sizeof(varname) vs. sizeof(type). - Allow an exception for nonconst reference parameters where convention dictates their use, such as for swap. - C++11: allow static_assert. - Require non-trivial fall-through between cases in switch statements to be annotated. Trivial fall-through includes consecutive case labels with no intervening code, and no comment is required in these cases. - C++11: allow constexpr. - Revise the "Integer Types" section to note type-width problems. - Clarify that the "arguments on subsequent lines" function call style is acceptable even when the 80-column limit doesn't require it. - Boost: allow part of Polygon. - C++11: allow <tuple>. Update Objective-C style guide to 2.52: - Fix ARC example to not imply the use of @private in .m files. - Add an example to the "Category Names" section. - Require that ARC-using files insert preprocessor directives that generate an error when compiling without ARC. - Fix spacing around the *s in the ARC example per the C++ style guide. Update Python style guide to 2.48: - Allow comments with URLs to exceed 80 characters per line. - Update outdated implicit-line-joining URLs. Update HTML/CSS style guide to 2.21: - Consistent use of title case. - Add new "Declaration Block Separation" section. - Add a CSS example to the "Capitalization" section. - Minor fixes to whitespace. Update JavaScript style to guide to 2.72: - Make it clear that the injunction against aliasing namespaces only applies to local aliases, not goog.scope. - Clarify the style guide's recommendation on array/object literals. - Add documentation on @private {type}, @protected {type}, and @const {type}. - Make JSDoc descriptions required only if not obvious. - Clarify that only private properties and methods need a trailing underscore. - Fix spelling of arv's name. Update Common Lisp style guide to 1.18: - Macro-defining macros are harder to understand for everyone, not just for the "uninitiated." There's no need to condescend. In all of the above style guides: - The guide source is now encoded as UTF-8. The numeric character references have been replaced with raw UTF-8-encoded characters.
2013-03-22 00:03:26 +08:00
<p>
Within comments, put long URLs on their own line if necessary.
</p>
<DIV class=""><PRE>Yes: <span class="external"></span># See details at
<span class="external"></span># http://www.example.com/us/developer/documentation/api/content/v2.0/csv_file_name_extension_full_specification.html</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span># See details at
<span class="external"></span># http://www.example.com/us/developer/documentation/api/content/\
<span class="external"></span># v2.0/csv_file_name_extension_full_specification.html</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Make note of the indentation of the elements in the line
Updating python style guide
2012-09-19 07:16:02 +08:00
continuation examples above; see the
Update C++ style guide to 3.231: - Clarify that sentence-like non-sentence comments are permitted. - Note that older code with incorrect #include ordering should be fixed. - Revamp the section on default function arguments. - Avoid explicitly recommending Init() methods. - C++11: permit "auto". - C++11: permit ">>" in place of "> >". - C++11: permit range-based "for". - C++11: permit variadic macros (already permitted as a C++03 extension). - C++11: permit "LL" and "ULL" literal suffixes (already permitted as a C++03 extension). - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - C++11: permit new features in <algorithm> and the portion of <numeric> that does not require initializer lists. - Revise rules on forward declarations: explicitly forbid forward-declared functions, do not mandate forward declarations, discourage forward-declared templates. - Remove the rule requiring "const" qualifiers for member functions to be on the same line as the closing parenthesis of the parameter list. - Fix typo: "unnamed namespaces." - C++11: permit local types as template parameters. - Fix typo: "unfamiliar." - Relax RTTI rules to permit its use, but warn about its abuse. - C++11: permit nullptr and nullptr_t. Revise text referring to NULL to refer more generically to null pointers. - Remove the "don't go crazy with const" rule. - Fix typo: "dir/foo2" should bee "dir2/foo2." - Remove reference to a specific GCC version. Update Objective-C style guide to 2.48: - Revise method declaration and invocation formatting rules for long names. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. Top-of-file comments are not required. - Fix dead link in the "nil Checks" section. - Cover ARC. - Specify that @private is only required for instance variables in header files. - Permit NSNumber literals. - Change the naming convention for instance variables from trailing underscore to leading underscore, allowing a wide exception for existing code and projects. - Fix description of BOOL with respect to its signedness. Update Python style guide to 2.45: - Recommend "pylint: disable" over "pylint: disable-msg." - Fix case-sensitive anchor. - Provide a better explanation of the problems with catch-all "except:." - Permit "map" and "filter" in absence of inlined lambdas. Update JavaScript style guide to 2.64: - Clarify rules for requiring and providing inner dependencies on classes. - Clarify semicolons for functions. - Note proper namespace and filename casing. - Fix typos: "@extends." - Permit parentheses to be omitted on unions. - Don't require method descriptions when obvious. - "in" is a keyword, put it in <code>. - New "Aliasing with goog.scope" section. - Rewrite the "Constants" section. - Remove the recommendation to use join() to build strings. - Add the "@expose" annotation. - Fix the "@suppress" example. - Remove reference alternate cast syntax. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - Say that "use strict" is not required. - Fix links to "optional" section. - Rewrite "JavaScript Types" section. - Fix typos: "parameterizes," "converted." - Prefer in-constructor field initialization. - Add a section on "delete" and null-assignment. - Add a note about optional JSDoc comments on enum values. - State explicitly that dot operators belong at the ends of lines. - Add "@dict" and "@struct" annotations. - Add links to the JavaScript Types section. - Require (rather than encourage) compiling. Update HTML/CSS style guide to 2.19: - Rephrased quotation guidelines. - Updated W3C I18N article reference. - Fixed revision number. Update styleguide.xsl to 1.34: - Fix error in RefreshVisibilityFromHashParam when a URL fragment points to a named anchor within a section, as used by the JavaScript style guide.
2012-11-29 04:26:27 +08:00
<a HREF="#Indentation">indentation</a>
A pyguide.html
2009-07-24 04:09:56 +08:00
section for explanation.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Parentheses" id="Parentheses">Parentheses</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Parentheses__button" name="link-Parentheses__button"><A href="?showone=Parentheses#Parentheses">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Parentheses')" name="Parentheses__button" id="Parentheses__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Use parentheses sparingly.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Parentheses__body" id="Parentheses__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Updating python style guide
2012-09-19 07:16:02 +08:00
Do not use them in return statements or conditional statements unless
using parentheses for implied line continuation. (See above.)
A pyguide.html
2009-07-24 04:09:56 +08:00
It is however fine to use parentheses around tuples.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>if foo:
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>bar()
<span class="external"></span>while x:
<span class="external"> </span>x = bar()
<span class="external"></span>if x and y:
<span class="external"> </span>bar()
<span class="external"></span>if not x:
<span class="external"> </span>bar()
<span class="external"></span>return foo
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>for (x, y) in dict.items(): ...</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>if (x):
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>bar()
<span class="external"></span>if not(x):
<span class="external"> </span>bar()
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>return (foo)</PRE></DIV>
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Indentation" id="Indentation">Indentation</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Indentation__button" name="link-Indentation__button"><A href="?showone=Indentation#Indentation">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Indentation')" name="Indentation__button" id="Indentation__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Indent your code blocks with <em>4 spaces</em>.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Indentation__body" id="Indentation__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Never use tabs or mix tabs and spaces.
In cases of implied line continuation, you should align wrapped elements
either vertically, as per the examples in the
<a HREF="#Line_length">line length</a> section; or using a hanging
indent of 4 spaces, in which case there should be no argument on
the first line.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: # Aligned with opening delimiter
A pyguide.html
2009-07-24 04:09:56 +08:00
foo = long_function_name(var_one, var_two,
var_three, var_four)
# 4-space hanging indent; nothing on first line
foo = long_function_name(
var_one, var_two, var_three,
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
var_four)</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span># Stuff on first line forbidden
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>foo = long_function_name(var_one, var_two,
<span class="external"></span> var_three, var_four)
<span class="external"></span># 2-space hanging indent forbidden
<span class="external"></span>foo = long_function_name(
<span class="external"></span> var_one, var_two, var_three,
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span> var_four)</PRE></DIV>
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Blank_Lines" id="Blank_Lines">Blank Lines</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Blank_Lines__button" name="link-Blank_Lines__button"><A href="?showone=Blank_Lines#Blank_Lines">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Blank_Lines')" name="Blank_Lines__button" id="Blank_Lines__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
Two blank lines between top-level definitions, one blank line
A pyguide.html
2009-07-24 04:09:56 +08:00
between method definitions.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Blank_Lines__body" id="Blank_Lines__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Two blank lines between top-level definitions, be they function
or class definitions. One blank line between method definitions
and between the <code>class</code> line and the first method.
Use single blank lines as you judge appropriate within functions or
methods.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Whitespace" id="Whitespace">Whitespace</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Whitespace__button" name="link-Whitespace__button"><A href="?showone=Whitespace#Whitespace">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Whitespace')" name="Whitespace__button" id="Whitespace__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Updating python style guide
2012-09-19 07:16:02 +08:00
Follow standard typographic rules for the use of spaces around
A pyguide.html
2009-07-24 04:09:56 +08:00
punctuation.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Whitespace__body" id="Whitespace__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
No whitespace inside parentheses, brackets or braces.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>spam(ham[1], {eggs: 2}, [])</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>spam( ham[ 1 ], { eggs: 2 }, [ ] )</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
No whitespace before a comma, semicolon, or colon. Do use
whitespace after a comma, semicolon, or colon except at the end
of the line.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>if x == 4:
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>print x, y
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>x, y = y, x</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>if x == 4 :
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"> </span>print x , y
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>x , y = y , x</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
No whitespace before the open paren/bracket that starts an argument list,
indexing or slicing.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>spam(1)</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>spam (1)</PRE></DIV>
<DIV class=""><PRE>Yes: <span class="external"></span>dict['key'] = list[index]</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>dict ['key'] = list [index]</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Surround binary operators with a single space on either side for
assignment (<code>=</code>), comparisons (<code>==, &lt;, &gt;, !=,
&lt;&gt;, &lt;=, &gt;=, in, not in, is, is not</code>), and Booleans
(<code>and, or, not</code>). Use your better judgment for the
insertion of spaces around arithmetic operators but always be
consistent about whitespace on either side of a binary operator.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>x == 1</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>x&lt;1</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Don't use spaces around the '=' sign when used to indicate a
keyword argument or a default parameter value.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>def complex(real, imag=0.0): return magic(r=real, i=imag)</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>def complex(real, imag = 0.0): return magic(r = real, i = imag)</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Don't use spaces to vertically align tokens on consecutive lines, since it
becomes a maintenance burden (applies to <code>:</code>, <code>#</code>,
<code>=</code>, etc.):
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes:
A pyguide.html
2009-07-24 04:09:56 +08:00
foo = 1000 # comment
long_name = 2 # comment that should not be aligned
dictionary = {
Updating python style guide
2012-09-19 07:16:02 +08:00
'foo': 1,
'long_name': 2,
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
}</PRE></DIV>
<DIV class=""><PRE class="badcode">No:
A pyguide.html
2009-07-24 04:09:56 +08:00
foo = 1000 # comment
long_name = 2 # comment that should not be aligned
dictionary = {
Updating python style guide
2012-09-19 07:16:02 +08:00
'foo' : 1,
'long_name': 2,
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
}</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
Update C++ style guide to 3.188: - Revise "Smart Pointers" section. - Clarify that it's OK to have spaces after '#' in a preprocessor directive, even though '#' itself must not be indented. - Revise "TODO Comments" section. - Fix wording. - Explicitly recommend foo.h be the first file #included by foo_test.cc. Update Objective-C style guide to 2.24: - Clarify the spacing of @property declarations. - Add "Overridden NSObject Method Placement" section. - Explicitly permit blank lines around @interface, @implementation, and @end. Update JavaScript style guide to 2.20: - Provide additional guidance with respect to the compiler. - Add {function(new:Type)} as a type syntax for constructors of Type. - Revise "Method and Function Comments" section. - Harmonize text and example in the "Passing Anonymous Functions" section. - Explicitly state that @param and @return types must be enclosed in braces. - Add documentation on the UNKNOWN type. - Replace a CODE_SNIPPET with BAD_CODE_SNIPPET in the "Internet Explorer's Conditional Comments" section. - Remove a redundant "Expand for more information" in the "Naming" section and fully spell out "information" in the "Code Formatting" section. - Provide a positive example in the "Multiline string literals" section. - Provide guidance for indentation within nested functions. Update Python style guide to 2.20: - Clarify shebang rule.
2011-03-30 04:30:47 +08:00
<a name="Python_Interpreter"></a>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class="">
Update C++ style guide to 3.188: - Revise "Smart Pointers" section. - Clarify that it's OK to have spaces after '#' in a preprocessor directive, even though '#' itself must not be indented. - Revise "TODO Comments" section. - Fix wording. - Explicitly recommend foo.h be the first file #included by foo_test.cc. Update Objective-C style guide to 2.24: - Clarify the spacing of @property declarations. - Add "Overridden NSObject Method Placement" section. - Explicitly permit blank lines around @interface, @implementation, and @end. Update JavaScript style guide to 2.20: - Provide additional guidance with respect to the compiler. - Add {function(new:Type)} as a type syntax for constructors of Type. - Revise "Method and Function Comments" section. - Harmonize text and example in the "Passing Anonymous Functions" section. - Explicitly state that @param and @return types must be enclosed in braces. - Add documentation on the UNKNOWN type. - Replace a CODE_SNIPPET with BAD_CODE_SNIPPET in the "Internet Explorer's Conditional Comments" section. - Remove a redundant "Expand for more information" in the "Naming" section and fully spell out "information" in the "Code Formatting" section. - Provide a positive example in the "Multiline string literals" section. - Provide guidance for indentation within nested functions. Update Python style guide to 2.20: - Clarify shebang rule.
2011-03-30 04:30:47 +08:00
<H3><A name="Shebang_Line" id="Shebang_Line">Shebang Line</A></H3>
<SPAN class="link_button" id="link-Shebang_Line__button" name="link-Shebang_Line__button"><A href="?showone=Shebang_Line#Shebang_Line">
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Shebang_Line')" name="Shebang_Line__button" id="Shebang_Line__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
Most <code>.py</code> files do not need to start with a
Update C++ style guide to 3.231: - Clarify that sentence-like non-sentence comments are permitted. - Note that older code with incorrect #include ordering should be fixed. - Revamp the section on default function arguments. - Avoid explicitly recommending Init() methods. - C++11: permit "auto". - C++11: permit ">>" in place of "> >". - C++11: permit range-based "for". - C++11: permit variadic macros (already permitted as a C++03 extension). - C++11: permit "LL" and "ULL" literal suffixes (already permitted as a C++03 extension). - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - C++11: permit new features in <algorithm> and the portion of <numeric> that does not require initializer lists. - Revise rules on forward declarations: explicitly forbid forward-declared functions, do not mandate forward declarations, discourage forward-declared templates. - Remove the rule requiring "const" qualifiers for member functions to be on the same line as the closing parenthesis of the parameter list. - Fix typo: "unnamed namespaces." - C++11: permit local types as template parameters. - Fix typo: "unfamiliar." - Relax RTTI rules to permit its use, but warn about its abuse. - C++11: permit nullptr and nullptr_t. Revise text referring to NULL to refer more generically to null pointers. - Remove the "don't go crazy with const" rule. - Fix typo: "dir/foo2" should bee "dir2/foo2." - Remove reference to a specific GCC version. Update Objective-C style guide to 2.48: - Revise method declaration and invocation formatting rules for long names. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. Top-of-file comments are not required. - Fix dead link in the "nil Checks" section. - Cover ARC. - Specify that @private is only required for instance variables in header files. - Permit NSNumber literals. - Change the naming convention for instance variables from trailing underscore to leading underscore, allowing a wide exception for existing code and projects. - Fix description of BOOL with respect to its signedness. Update Python style guide to 2.45: - Recommend "pylint: disable" over "pylint: disable-msg." - Fix case-sensitive anchor. - Provide a better explanation of the problems with catch-all "except:." - Permit "map" and "filter" in absence of inlined lambdas. Update JavaScript style guide to 2.64: - Clarify rules for requiring and providing inner dependencies on classes. - Clarify semicolons for functions. - Note proper namespace and filename casing. - Fix typos: "@extends." - Permit parentheses to be omitted on unions. - Don't require method descriptions when obvious. - "in" is a keyword, put it in <code>. - New "Aliasing with goog.scope" section. - Rewrite the "Constants" section. - Remove the recommendation to use join() to build strings. - Add the "@expose" annotation. - Fix the "@suppress" example. - Remove reference alternate cast syntax. - Reflect the revised copyright and author line policy: copyright notices are not required, but license boilerplate may still be used (and generally contains a copyright notice). Author lines are not required. - Say that "use strict" is not required. - Fix links to "optional" section. - Rewrite "JavaScript Types" section. - Fix typos: "parameterizes," "converted." - Prefer in-constructor field initialization. - Add a section on "delete" and null-assignment. - Add a note about optional JSDoc comments on enum values. - State explicitly that dot operators belong at the ends of lines. - Add "@dict" and "@struct" annotations. - Add links to the JavaScript Types section. - Require (rather than encourage) compiling. Update HTML/CSS style guide to 2.19: - Rephrased quotation guidelines. - Updated W3C I18N article reference. - Fixed revision number. Update styleguide.xsl to 1.34: - Fix error in RefreshVisibilityFromHashParam when a URL fragment points to a named anchor within a section, as used by the JavaScript style guide.
2012-11-29 04:26:27 +08:00
<code>#!</code> line. Start the main file of a program with
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
<code>#!/usr/bin/python</code>.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
Update C++ style guide to 3.188: - Revise "Smart Pointers" section. - Clarify that it's OK to have spaces after '#' in a preprocessor directive, even though '#' itself must not be indented. - Revise "TODO Comments" section. - Fix wording. - Explicitly recommend foo.h be the first file #included by foo_test.cc. Update Objective-C style guide to 2.24: - Clarify the spacing of @property declarations. - Add "Overridden NSObject Method Placement" section. - Explicitly permit blank lines around @interface, @implementation, and @end. Update JavaScript style guide to 2.20: - Provide additional guidance with respect to the compiler. - Add {function(new:Type)} as a type syntax for constructors of Type. - Revise "Method and Function Comments" section. - Harmonize text and example in the "Passing Anonymous Functions" section. - Explicitly state that @param and @return types must be enclosed in braces. - Add documentation on the UNKNOWN type. - Replace a CODE_SNIPPET with BAD_CODE_SNIPPET in the "Internet Explorer's Conditional Comments" section. - Remove a redundant "Expand for more information" in the "Naming" section and fully spell out "information" in the "Code Formatting" section. - Provide a positive example in the "Multiline string literals" section. - Provide guidance for indentation within nested functions. Update Python style guide to 2.20: - Clarify shebang rule.
2011-03-30 04:30:47 +08:00
<DIV class=""><DIV class="stylepoint_body" name="Shebang_Line__body" id="Shebang_Line__body" style="display: none">
<p>
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
This line is used by the kernel to find the Python interpreter, but is
ignored by Python when importing modules. It is only necessary on a
file that will be executed directly.
Update C++ style guide to 3.188: - Revise "Smart Pointers" section. - Clarify that it's OK to have spaces after '#' in a preprocessor directive, even though '#' itself must not be indented. - Revise "TODO Comments" section. - Fix wording. - Explicitly recommend foo.h be the first file #included by foo_test.cc. Update Objective-C style guide to 2.24: - Clarify the spacing of @property declarations. - Add "Overridden NSObject Method Placement" section. - Explicitly permit blank lines around @interface, @implementation, and @end. Update JavaScript style guide to 2.20: - Provide additional guidance with respect to the compiler. - Add {function(new:Type)} as a type syntax for constructors of Type. - Revise "Method and Function Comments" section. - Harmonize text and example in the "Passing Anonymous Functions" section. - Explicitly state that @param and @return types must be enclosed in braces. - Add documentation on the UNKNOWN type. - Replace a CODE_SNIPPET with BAD_CODE_SNIPPET in the "Internet Explorer's Conditional Comments" section. - Remove a redundant "Expand for more information" in the "Naming" section and fully spell out "information" in the "Code Formatting" section. - Provide a positive example in the "Multiline string literals" section. - Provide guidance for indentation within nested functions. Update Python style guide to 2.20: - Clarify shebang rule.
2011-03-30 04:30:47 +08:00
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
Update C++ style guide to 3.188: - Revise "Smart Pointers" section. - Clarify that it's OK to have spaces after '#' in a preprocessor directive, even though '#' itself must not be indented. - Revise "TODO Comments" section. - Fix wording. - Explicitly recommend foo.h be the first file #included by foo_test.cc. Update Objective-C style guide to 2.24: - Clarify the spacing of @property declarations. - Add "Overridden NSObject Method Placement" section. - Explicitly permit blank lines around @interface, @implementation, and @end. Update JavaScript style guide to 2.20: - Provide additional guidance with respect to the compiler. - Add {function(new:Type)} as a type syntax for constructors of Type. - Revise "Method and Function Comments" section. - Harmonize text and example in the "Passing Anonymous Functions" section. - Explicitly state that @param and @return types must be enclosed in braces. - Add documentation on the UNKNOWN type. - Replace a CODE_SNIPPET with BAD_CODE_SNIPPET in the "Internet Explorer's Conditional Comments" section. - Remove a redundant "Expand for more information" in the "Naming" section and fully spell out "information" in the "Code Formatting" section. - Provide a positive example in the "Multiline string literals" section. - Provide guidance for indentation within nested functions. Update Python style guide to 2.20: - Clarify shebang rule.
2011-03-30 04:30:47 +08:00
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class="">
<H3><A name="Comments" id="Comments">Comments</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Comments__button" name="link-Comments__button"><A href="?showone=Comments#Comments">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Comments')" name="Comments__button" id="Comments__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Be sure to use the right style for module, function, method and in-line
comments.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Comments__body" id="Comments__body" style="display: none">
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<P class="">
<SPAN class="stylepoint_subsection">Doc Strings</SPAN>
<p>
Python has a unique commenting style using doc strings. A doc
string is a string that is the first statement in a package,
module, class or function. These strings can be extracted
automatically through the <code>__doc__</code> member of the
object and are used by <code>pydoc</code>. (Try running
<code>pydoc</code> on your module to see how it looks.) Our
convention for doc strings is to use the three double-quote
format for strings. A doc string should be organized as a
summary line (one physical line) terminated by a period,
question mark, or exclamation point, followed by a blank line,
followed by the rest of the doc string starting at the same
cursor position as the first quote of the first line. There are
more formatting guidelines for doc strings below.
</p>
</P>
<P class="">
<SPAN class="stylepoint_subsection">Modules</SPAN>
<p>
Updating python style guide
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Every file should contain license boilerplate.
Choose the appropriate boilerplate for the license used by the project
(for example, Apache 2.0, BSD, LGPL, GPL)
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</p>
</P>
<P class="">
<SPAN class="stylepoint_subsection">Functions and Methods</SPAN>
<p>
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
As used in this section "function" applies to methods, function, and
generators.
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</p>
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
<p>
A function must have a docstring, unless it meets all of the following
criteria:
<ul>
<li>not externally visible</li>
<li>very short</li>
<li>obvious</li>
</ul>
</p>
<p>
A docstring should give enough information to write a call to the function
without reading the function's code. A docstring should describe the
function's calling syntax and its semantics, not its implementation. For
tricky code, comments alongside the code are more appropriate than using
docstrings.
</p>
<p>
Certain aspects of a function should be documented in special sections,
listed below. Each section begins with a heading line, which ends with a
colon. Sections should be indented two spaces, except for the heading.
</p>
<dl>
<dt>Args:</dt>
<dd>
List each parameter by name. A description should follow the name, and
be separated by a colon and a space. If the description is too long to
fit on a single 80-character line, use a hanging indent of 2 or 4 spaces
(be consistent with the rest of the file).
<p>
The description should mention required type(s) and the meaning of
the argument.
</p>
<p>
If a function accepts *foo (variable length argument lists) and/or
**bar (arbitrary keyword arguments), they should be listed as *foo and
**bar.
</p>
</dd>
<dt>Returns: (or Yields: for generators)</dt>
<dd>
Describe the type and semantics of the return value. If the function
only returns None, this section is not required.
</dd>
<dt>Raises:</dt>
<dd>
List all exceptions that are relevant to the interface.
</dd>
</dl>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>def fetch_bigtable_rows(big_table, keys, other_silly_variable=None):
<span class="external"> </span>"""Fetches rows from a Bigtable.
<span class="external"> </span>Retrieves rows pertaining to the given keys from the Table instance
<span class="external"> </span>represented by big_table. Silly things may happen if
<span class="external"> </span>other_silly_variable is not None.
<span class="external"> </span>Args:
<span class="external"> </span>big_table: An open Bigtable Table instance.
<span class="external"> </span>keys: A sequence of strings representing the key of each table row
<span class="external"> </span> to fetch.
<span class="external"> </span>other_silly_variable: Another optional variable, that has a much
<span class="external"> </span> longer name than the other args, and which does nothing.
<span class="external"> </span>Returns:
<span class="external"> </span>A dict mapping keys to the corresponding table row data
<span class="external"> </span>fetched. Each row is represented as a tuple of strings. For
<span class="external"> </span>example:
<span class="external"> </span>{'Serak': ('Rigel VII', 'Preparer'),
<span class="external"> </span> 'Zim': ('Irk', 'Invader'),
<span class="external"> </span> 'Lrrr': ('Omicron Persei 8', 'Emperor')}
<span class="external"> </span>If a key from the keys argument is missing from the dictionary,
<span class="external"> </span>then that row was not found in the table.
<span class="external"> </span>Raises:
<span class="external"> </span>IOError: An error occurred accessing the bigtable.Table object.
<span class="external"> </span>"""
<span class="external"> </span>pass
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
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</P>
<P class="">
<SPAN class="stylepoint_subsection">Classes</SPAN>
<p>
Classes should have a doc string below the class definition describing
the class. If your class has public attributes, they should be documented
here in an Attributes section and follow the same formatting as a
function's Args section.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span>class SampleClass(object):
<span class="external"> </span>"""Summary of class here.
<span class="external"> </span>Longer class information....
<span class="external"> </span>Longer class information....
<span class="external"> </span>Attributes:
<span class="external"> </span>likes_spam: A boolean indicating if we like SPAM or not.
<span class="external"> </span>eggs: An integer count of the eggs we have laid.
<span class="external"> </span>"""
<span class="external"> </span>def __init__(self, likes_spam=False):
<span class="external"> </span>"""Inits SampleClass with blah."""
<span class="external"> </span>self.likes_spam = likes_spam
<span class="external"> </span>self.eggs = 0
<span class="external"> </span>def public_method(self):
<span class="external"> </span>"""Performs operation blah."""
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
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</P>
<P class="">
<SPAN class="stylepoint_subsection">Block and Inline Comments</SPAN>
<p>
The final place to have comments is in tricky parts of the
Updating python style guide
2012-09-19 07:16:02 +08:00
code. If you're going to have to explain it at the next
<a HREF="http://en.wikipedia.org/wiki/Code_review">code review</a>,
you should comment it now. Complicated operations get a few lines of
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comments before the operations
commence. Non-obvious ones get comments at the end of the line.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
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<span class="external"></span># We use a weighted dictionary search to find out where i is in
<span class="external"></span># the array. We extrapolate position based on the largest num
<span class="external"></span># in the array and the array size and then do binary search to
<span class="external"></span># get the exact number.
<span class="external"></span>if i &amp; (i-1) == 0: # true iff i is a power of 2
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
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<p>
To improve legibility, these comments should be at least 2 spaces away
from the code.
</p>
<p>
On the other hand, never describe the code. Assume the person
reading the code knows Python (though not what you're trying to
do) better than you do.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE class="badcode">
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span># BAD COMMENT: Now go through the b array and make sure whenever i occurs
<span class="external"></span># the next element is i+1
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Classes" id="Classes">Classes</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Classes__button" name="link-Classes__button"><A href="?showone=Classes#Classes">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Classes')" name="Classes__button" id="Classes__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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If a class inherits from no other base classes, explicitly inherit
from <code>object</code>. This also applies to nested classes.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Classes__body" id="Classes__body" style="display: none">
<DIV class=""><PRE>Yes: <span class="external"></span>class SampleClass(object):
A pyguide.html
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<span class="external"> </span>pass
<span class="external"></span>class OuterClass(object):
<span class="external"> </span>class InnerClass(object):
<span class="external"> </span>pass
<span class="external"></span>class ChildClass(ParentClass):
<span class="external"> </span>"""Explicitly inherits from another class already."""
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
Updating python style guide
2012-09-19 07:16:02 +08:00
<DIV class=""><PRE class="badcode">No: <span class="external"></span>class SampleClass:
<span class="external"> </span>pass
A pyguide.html
2009-07-24 04:09:56 +08:00
Updating python style guide
2012-09-19 07:16:02 +08:00
<span class="external"></span>class OuterClass:
<span class="external"> </span>class InnerClass:
<span class="external"> </span>pass
<span class="external"></span>
</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>Inheriting from <code>object</code> is needed to make properties work
Updating python style guide
2012-09-19 07:16:02 +08:00
properly, and it will protect your code from one particular potential
A pyguide.html
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incompatibility with Python 3000. It also defines
special methods that implement the default semantics of objects including
<code>__new__</code>, <code>__init__</code>, <code>__delattr__</code>,
<code>__getattribute__</code>, <code>__setattr__</code>,
<code>__hash__</code>, <code>__repr__</code>, and <code>__str__</code>.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Strings" id="Strings">Strings</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Strings__button" name="link-Strings__button"><A href="?showone=Strings#Strings">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Strings')" name="Strings__button" id="Strings__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
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Use the <code>%</code> operator for formatting strings,
even when the parameters are all strings. Use your best judgement
to decide between <code>+</code> and <code>%</code> though.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Strings__body" id="Strings__body" style="display: none">
Updating python style guide
2012-09-19 07:16:02 +08:00
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>x = a + b
A pyguide.html
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<span class="external"></span>x = '%s, %s!' % (imperative, expletive)
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>x = 'name: %s; score: %d' % (name, n)</PRE></DIV>
Updating python style guide
2012-09-19 07:16:02 +08:00
<DIV class=""><PRE class="badcode">No: <span class="external"></span>x = '%s%s' % (a, b) # use + in this case
<span class="external"></span>x = imperative + ', ' + expletive + '!'
<span class="external"></span>x = 'name: ' + name + '; score: ' + str(n)</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Avoid using the <code>+</code> and <code>+=</code> operators to
accumulate a string within a loop. Since strings are immutable, this
creates unnecessary temporary objects and results in quadratic rather
than linear running time. Instead, add each substring to a list and
<code>''.join</code> the list after the loop terminates (or, write each
substring to a <code>cStringIO.StringIO</code> buffer).
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>items = ['&lt;table&gt;']
A pyguide.html
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<span class="external"></span>for last_name, first_name in employee_list:
<span class="external"> </span>items.append('&lt;tr&gt;&lt;td&gt;%s, %s&lt;/td&gt;&lt;/tr&gt;' % (last_name, first_name))
<span class="external"></span>items.append('&lt;/table&gt;')
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>employee_table = ''.join(items)</PRE></DIV>
Updating python style guide
2012-09-19 07:16:02 +08:00
<DIV class=""><PRE class="badcode">No: <span class="external"></span>employee_table = '&lt;table&gt;'
<span class="external"></span>for last_name, first_name in employee_list:
<span class="external"> </span>employee_table += '&lt;tr&gt;&lt;td&gt;%s, %s&lt;/td&gt;&lt;/tr&gt;' % (last_name, first_name)
<span class="external"></span>employee_table += '&lt;/table&gt;'</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Use <code>"""</code> for multi-line strings rather than
<code>'''</code>. Note, however, that it is often cleaner to
use implicit line joining since multi-line strings do
not flow with the indentation of the rest of the program:
</p>
Updating python style guide
2012-09-19 07:16:02 +08:00
<DIV class=""><PRE>Ye<span class="external"></span>s:
<span class="external"></span>print ("This is much nicer.\n"
<span class="external"></span> "Do it this way.\n")</PRE></DIV>
<DIV class=""><PRE class="badcode"> No<span class="external"></span>:
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>print """This is pretty ugly.
Don'<span class="external"></span>t do this.
"""<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
Updating python style guide
2012-09-19 07:16:02 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Files_and_Sockets" id="Files_and_Sockets">Files and Sockets</A></H3>
<SPAN class="link_button" id="link-Files_and_Sockets__button" name="link-Files_and_Sockets__button"><A href="?showone=Files_and_Sockets#Files_and_Sockets">
link
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Files_and_Sockets')" name="Files_and_Sockets__button" id="Files_and_Sockets__button">▶</SPAN>
<DIV style="display:inline;" class="">
Explicitly close files and sockets when done with them.
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Files_and_Sockets__body" id="Files_and_Sockets__body" style="display: none">
<p>
Leaving files, sockets or other file-like objects open unnecessarily
has many downsides, including:
<ul>
<li>They may consume limited system resources, such as file
descriptors. Code that deals with many such objects may exhaust
those resources unnecessarily if they're not returned to the
system promptly after use.</li>
<li>Holding files open may prevent other actions being performed on
them, such as moves or deletion.</li>
<li>Files and sockets that are shared throughout a program may
inadvertantly be read from or written to after logically being
closed. If they are actually closed, attempts to read or write
from them will throw exceptions, making the problem known
sooner.</li>
</ul>
</p>
<p>
Furthermore, while files and sockets are automatically closed when the
file object is destructed, tying the life-time of the file object to
the state of the file is poor practice, for several reasons:
<ul>
<li>There are no guarantees as to when the runtime will actually run
the file's destructor. Different Python implementations use
different memory management techniques, such as delayed Garbage
Collection, which may increase the object's lifetime arbitrarily
and indefinitely.</li>
<li>Unexpected references to the file may keep it around longer than
intended (e.g. in tracebacks of exceptions, inside globals,
etc).</li>
</ul>
</p>
<p>
The preferred way to manage files is using the <a HREF="http://docs.python.org/reference/compound_stmts.html#the-with-statement">
"with" statement</a>:
</p>
<DIV class=""><PRE>
<span class="external"></span>with open("hello.txt") as hello_file:
<span class="external"> </span>for line in hello_file:
<span class="external"> </span>print line</PRE></DIV>
<p>
For file-like objects that do not support the "with" statement, use
contextlib.closing():
</p>
<DIV class=""><PRE>
<span class="external"></span>import contextlib
<span class="external"></span>with contextlib.closing(urllib.urlopen("http://www.python.org/")) as front_page:
<span class="external"> </span>for line in front_page:
<span class="external"> </span>print line</PRE></DIV>
<p>
Legacy AppEngine code using Python 2.5 may enable the "with" statement
using "from __future__ import with_statement".
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="TODO_Comments" id="TODO_Comments">TODO Comments</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-TODO_Comments__button" name="link-TODO_Comments__button"><A href="?showone=TODO_Comments#TODO_Comments">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('TODO_Comments')" name="TODO_Comments__button" id="TODO_Comments__button">▶</SPAN>
<DIV style="display:inline;" class="">
Use <code>TODO</code> comments for code that is temporary, a
short-term solution, or good-enough but not perfect.
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="TODO_Comments__body" id="TODO_Comments__body" style="display: none">
<p>
<code>TODO</code>s should include the string <code>TODO</code> in
all caps, followed by the
name, e-mail address, or other
identifier
of the person who can best provide context about the problem
referenced by the <code>TODO</code>,
in parentheses. A colon is optional. A comment explaining what there
is to do is required. The main purpose is to have
a consistent <code>TODO</code> format that can be searched to find the
person who can provide more details upon request. A
<code>TODO</code> is not a commitment that the person referenced
will fix the problem. Thus when you create a <code>TODO</code>, it is
almost always your
name
that is given.
</p>
A pyguide.html
2009-07-24 04:09:56 +08:00
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
<DIV class=""><PRE># TODO(kl@gmail.com): Use a "*" here for string repetition.
# TODO(Zeke) Change this to use relations.</PRE></DIV>
<p>
If your <code>TODO</code> is of the form "At a future date do
something" make sure that you either include a very specific
date ("Fix by November 2009") or a very specific event
("Remove this code when all clients can handle XML responses.").
</p>
</DIV></DIV>
</DIV>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class="">
<H3><A name="Imports_formatting" id="Imports_formatting">Imports formatting</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Imports_formatting__button" name="link-Imports_formatting__button"><A href="?showone=Imports_formatting#Imports_formatting">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Imports_formatting')" name="Imports_formatting__button" id="Imports_formatting__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Imports should be on separate lines.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Imports_formatting__body" id="Imports_formatting__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
E.g.:
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Yes: <span class="external"></span>import os
<span class="external"></span>import sys</PRE></DIV>
<DIV class=""><PRE class="badcode">No: <span class="external"></span>import os, sys</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
Imports are always put at the top of the file, just after any
module comments and doc strings and before module globals and
constants. Imports should be grouped with the order being most generic
to least generic:
</p>
<ul>
<li>standard library imports</li>
<li>third-party imports</li>
<li>application-specific imports</li>
</ul>
<p>
Within each grouping, imports should be sorted lexicographically,
ignoring case, according to each module's full package path.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>import foo
<span class="external"></span>from foo import bar
<span class="external"></span>from foo.bar import baz
<span class="external"></span>from foo.bar import Quux
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>from Foob import ar</PRE></DIV>
A pyguide.html
2009-07-24 04:09:56 +08:00
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Statements" id="Statements">Statements</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Statements__button" name="link-Statements__button"><A href="?showone=Statements#Statements">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Statements')" name="Statements__button" id="Statements__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
Generally only one statement per line.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Statements__body" id="Statements__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
However, you may put the
result of a test on the same line as the test only if the entire
statement fits on one line. In particular, you can never do so
with <code>try</code>/<code>except</code> since the
<code>try</code> and <code>except</code> can't both fit on the
same line, and you can only do so with an <code>if</code> if
there is no <code>else</code>.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV class=""><PRE>Ye<span class="external"></span>s:
A pyguide.html
2009-07-24 04:09:56 +08:00
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<span class="external"></span>if foo: bar(foo)</PRE></DIV>
<DIV class=""><PRE class="badcode">No<span class="external"></span>:
A pyguide.html
2009-07-24 04:09:56 +08:00
<span class="external"></span>if foo: bar(foo)
<span class="external"></span>else: baz(foo)
<span class="external"></span>try: bar(foo)
<span class="external"></span>except ValueError: baz(foo)
<span class="external"></span>try:
<span class="external"> </span>bar(foo)
<span class="external"></span>except ValueError: baz(foo)
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</PRE></DIV>
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Access_Control" id="Access_Control">Access Control</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Access_Control__button" name="link-Access_Control__button"><A href="?showone=Access_Control#Access_Control">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Access_Control')" name="Access_Control__button" id="Access_Control__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
A pyguide.html
2009-07-24 04:09:56 +08:00
If an accessor function would be trivial you should use public variables
Updating python style guide
2012-09-19 07:16:02 +08:00
instead of accessor functions to avoid the extra cost of function
calls in Python. When more functionality is added you can use
A pyguide.html
2009-07-24 04:09:56 +08:00
<code>property</code> to keep the syntax consistent.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Access_Control__body" id="Access_Control__body" style="display: none">
A pyguide.html
2009-07-24 04:09:56 +08:00
<p>
On the other hand, if access is more complex, or the cost of accessing
the variable is significant, you should use function calls (following the
<a HREF="#naming">Naming</a> guidelines) such as <code>get_foo()</code>
and <code>set_foo()</code>. If the past behavior allowed access through a
property, do not bind the new accessor functions to the property. Any
code still attempting to access the variable by the old method should
break visibly so they are made aware of the change in complexity.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Naming" id="Naming">Naming</A></H3>
Update Python style guide with styleguide.xsl r51.
2010-08-05 01:46:16 +08:00
<SPAN class="link_button" id="link-Naming__button" name="link-Naming__button"><A href="?showone=Naming#Naming">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Naming')" name="Naming__button" id="Naming__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
<DIV style="display:inline;" class="">
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
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<code>module_name, package_name, ClassName,
method_name, ExceptionName,
function_name, GLOBAL_CONSTANT_NAME,
global_var_name, instance_var_name, function_parameter_name,
local_var_name.</code>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Naming__body" id="Naming__body" style="display: none">
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<P class="">
<SPAN class="stylepoint_subsection">Names to Avoid</SPAN>
<ul>
<li>single character names except for counters or iterators</li>
<li>dashes (<code>-</code>) in any package/module name</li>
<li>
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<code>__double_leading_and_trailing_underscore__</code> names
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(reserved by Python)</li>
</ul>
</P>
<P class="">
<SPAN class="stylepoint_subsection">Naming Convention</SPAN>
<ul>
<li>
"Internal" means internal to a module or protected
or private within a class.</li>
<li>
Prepending a single underscore (<code>_</code>) has some
support for protecting module variables and functions (not included
with <code>import * from</code>). Prepending a double underscore
(<code>__</code>) to an instance variable or method
effectively serves to make the variable or method private to its class
(using name mangling).</li>
<li>
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Place related classes and top-level functions together in a
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module. Unlike Java,
there is no need to limit yourself to one class per module.</li>
<li>
Use CapWords for class names, but lower_with_under.py for module names.
Although there are many existing modules named CapWords.py, this is now
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discouraged because it's confusing when the module happens to be
named after a class. ("wait -- did I write
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<code>import StringIO</code> or <code>from StringIO import
StringIO</code>?")</li>
</ul>
</P>
<P class="">
<SPAN class="stylepoint_subsection">Guidelines derived from Guido's Recommendations</SPAN>
<table rules="all" border="1" cellspacing="2" cellpadding="2">
<tr>
<th>Type</th>
<th>Public</th>
<th>Internal</th>
</tr>
<tr>
<td>Packages</td>
<td><code>lower_with_under</code></td>
<td></td>
</tr>
<tr>
<td>Modules</td>
<td><code>lower_with_under</code></td>
<td><code>_lower_with_under</code></td>
</tr>
<tr>
<td>Classes</td>
<td><code>CapWords</code></td>
<td><code>_CapWords</code></td>
</tr>
<tr>
<td>Exceptions</td>
<td><code>CapWords</code></td>
<td></td>
</tr>
<tr>
<td>Functions</td>
<td><code>lower_with_under()</code></td>
<td><code>_lower_with_under()</code></td>
</tr>
<tr>
<td>Global/Class Constants</td>
<td><code>CAPS_WITH_UNDER</code></td>
<td><code>_CAPS_WITH_UNDER</code></td>
</tr>
<tr>
<td>Global/Class Variables</td>
<td><code>lower_with_under</code></td>
<td><code>_lower_with_under</code></td>
</tr>
<tr>
<td>Instance Variables</td>
<td><code>lower_with_under</code></td>
<td><code>_lower_with_under (protected) or __lower_with_under (private)</code></td>
</tr>
<tr>
<td>Method Names</td>
<td><code>lower_with_under()</code></td>
<td><code>_lower_with_under() (protected) or __lower_with_under() (private)</code></td>
</tr>
<tr>
<td>Function/Method Parameters</td>
<td><code>lower_with_under</code></td>
<td></td>
</tr>
<tr>
<td>Local Variables</td>
<td><code>lower_with_under</code></td>
<td></td>
</tr>
</table>
</P>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
2009-12-04 06:25:38 +08:00
</DIV></DIV>
</DIV>
<DIV class="">
<H3><A name="Main" id="Main">Main</A></H3>
Update Python style guide with styleguide.xsl r51.
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<SPAN class="link_button" id="link-Main__button" name="link-Main__button"><A href="?showone=Main#Main">
link
Update C++ style guide to 3.199: - Update an example to omit the blank line between C and C++ #includes. - Rewrite the paragraph about #include ordering. - Clarify namespace closing comments. - Discourage const references for input arguments which are aliased beyond the scope of the function call. - Replace all '&' with '&amp;'. - Clarify that interfaces must have virtual destructors. - Add an explicit example for |else if|. - C++11 updates. Update Objective-C style guide to 2.36: - Remove requirement to list @dynamic implementations. - Remove requirement to never synthesize CFType properties, since they may be retained on 10.6. - Use __weak and __strong type declaration modifiers rather than comments. - Make the copyright/license information consistent. - An example initializer comment revealed too much about the implementation. - Correct spelling mistakes. - Fix names that didn't follow Cocoa conventions. - Fix examples to conform to style. - Add a section about no braces for empty interfaces. - Add a section about automatically synthesized instance variables. - Codify avoidance of accessors in -init and -dealloc methods. - Changes for the 80-column rule. - Weaken the language around object ownership type qualifiers. - Document the rules for formatting blocks. Update JavaScript style guide to 2.27: - Introduce EcmaScript 5 Strict verbiage. - Add a note about private constructors. - Simplify explanations about JSDoc comments. - Sort the JSDoc tags. - Remove the sections about type-checking now that the JSDoc tags and JS types are no longer one table. - Convert <tt> to <code>, because the XSL processor eats <tt>. - Add @suppress. - Mark @inheritDoc deprecated in favor of @override. - Add a section about inner classes and enums being defined in the same file as the top-level class they are defined on. Update Python style guide to 2.28: - Change "Naming" summary to match body. - Make the prohibition against backslash line continuation explicit. - Update the TODO section to match the C++ style guide. - Declare Python code without a shebang line to be stylish. - Clarify rules on function docstrings. - Fix spelling errors. - Update with styleguide.xsl 1.33. Update styleguide.xsl to 1.33: - Clean up style guide JS. - Links to anchor tags auto-expand.
2011-11-05 00:55:22 +08:00
</A></SPAN><SPAN class="showhide_button" onclick="javascript:ShowHideByName('Main')" name="Main__button" id="Main__button">▶</SPAN>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV style="display:inline;" class="">
Updating python style guide
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Even a file meant to be used as a script should be importable and a
mere import should not have the side effect of executing the script's
main functionality. The main functionality should be in a main()
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function.
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</DIV>
<DIV class=""><DIV class="stylepoint_body" name="Main__body" id="Main__body" style="display: none">
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<p>
In Python,
<code>pychecker</code>, <code>pydoc</code>, and unit tests
require modules to be importable. Your code should always check
<code>if __name__ == '__main__'</code> before executing your
main program so that the main program is not executed when the
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module is imported.
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</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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<DIV class=""><PRE>
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<span class="external"></span>def main():
<span class="external"> </span>...
<span class="external"></span>if __name__ == '__main__':
<span class="external"> </span>main()
<span class="external"></span>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</PRE></DIV>
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<p>
All code at the top level will be executed when the module is
imported. Be careful not to call functions, create objects, or
perform other operations that should not be executed when the
file is being <code>pycheck</code>ed or <code>pydoc</code>ed.
</p>
Update C++ style guide to 3.154: - Add call_traits to the set of allowed boost libraries. - Add an exception to the rule against default arguments to cover the useful case of simulating variadic functions. - Discourage the usage of ## in macros. - Clarify example: it's acceptable to declare two parameters on one line even if they don't all fit on that one line. - Fix a typo ("make use symmetric spacing"). - Change bitwise AND to logical AND in a condition. Update styleguide.xsl to 1.27: - Change a bunch of SPANs into DIVs. Update Python style guide to 2.15: - Apply styleguide.xsl 1.27, changing a bunch of SPANs into DIVs.
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</DIV></DIV>
</DIV>
</DIV>
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<H2>Parting Words</H2>
<p>
<em>BE CONSISTENT</em>.
</p>
<p>
If you're editing code, take a few minutes to look at the code
around you and determine its style. If they use spaces around
all their arithmetic operators, you should too. If their
comments have little boxes of hash marks around them, make your
comments have little boxes of hash marks around them too.
</p>
<p>
The point of having style guidelines is to have a common vocabulary
of coding so people can concentrate on what you're saying rather
than on how you're saying it. We present global style rules here so
people know the vocabulary, but local style is also important. If
code you add to a file looks drastically different from the existing
code around it, it throws readers out of their rhythm when they go to
read it. Avoid this.
</p>
<p align="right">
Update C++ style guide to 3.245: - Relax the rule for sizeof(varname) vs. sizeof(type). - Allow an exception for nonconst reference parameters where convention dictates their use, such as for swap. - C++11: allow static_assert. - Require non-trivial fall-through between cases in switch statements to be annotated. Trivial fall-through includes consecutive case labels with no intervening code, and no comment is required in these cases. - C++11: allow constexpr. - Revise the "Integer Types" section to note type-width problems. - Clarify that the "arguments on subsequent lines" function call style is acceptable even when the 80-column limit doesn't require it. - Boost: allow part of Polygon. - C++11: allow <tuple>. Update Objective-C style guide to 2.52: - Fix ARC example to not imply the use of @private in .m files. - Add an example to the "Category Names" section. - Require that ARC-using files insert preprocessor directives that generate an error when compiling without ARC. - Fix spacing around the *s in the ARC example per the C++ style guide. Update Python style guide to 2.48: - Allow comments with URLs to exceed 80 characters per line. - Update outdated implicit-line-joining URLs. Update HTML/CSS style guide to 2.21: - Consistent use of title case. - Add new "Declaration Block Separation" section. - Add a CSS example to the "Capitalization" section. - Minor fixes to whitespace. Update JavaScript style to guide to 2.72: - Make it clear that the injunction against aliasing namespaces only applies to local aliases, not goog.scope. - Clarify the style guide's recommendation on array/object literals. - Add documentation on @private {type}, @protected {type}, and @const {type}. - Make JSDoc descriptions required only if not obvious. - Clarify that only private properties and methods need a trailing underscore. - Fix spelling of arv's name. Update Common Lisp style guide to 1.18: - Macro-defining macros are harder to understand for everyone, not just for the "uninitiated." There's no need to condescend. In all of the above style guides: - The guide source is now encoded as UTF-8. The numeric character references have been replaced with raw UTF-8-encoded characters.
2013-03-22 00:03:26 +08:00
Revision 2.48
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</p>
<address>
Amit Patel<br>
Antoine Picard<br>
Eugene Jhong<br>
Jeremy Hylton<br>
Matt Smart<br>
Mike Shields<br>
</address>
</BODY>
</HTML>
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