- Change formatting rules of braced initializers.
- Permit use of constexpr and allow constexpr global variables.
- Allow all C++11 features except for those that are specifically banned.
- Fix/add C99 format specifiers for ptrdiff_t and ssize_t.
- Add lambda expressions to the list of explicitly banned C++11 features.
- Relax "return type is always on the same line as the function name" rule.
- Allow unique_ptr, discourage ownership transfer. Allow noncopyable std::move.
- Allow system-specific includes after other includes.
- Add boost/math/distributions to the set of permitted Boost libraries.
Update Objective-C style guide to 2.59:
- Use instancetype as return type for example init methods.
- Remove invalid +stringWithInt: call.
- Remove reference to pre-Objective-C 2.0 declaration requirements.
- Remove reference to Objective-C exception macros.
- Remove reference to informal protocols as an alternative to optional methods.
- Class headers should include comments documenting non-trivial interfaces.
- Don't specify that blocks are preferable to methods as callbacks.
- Specify "strong" and "weak" as comments for non-Objective-C pointers.
- Replace improper reference to ownership of a retained object.
- Clarify some aspects of method ordering rules.
- Prefixes are required for shared code and optional for applications.
- Clarify that nil pointers are safe as receivers, not necessarily parameters.
- Clarify that delegate pointers should typically be zeroing weak pointers.
- Allow a 100-column limit, except for projects that choose to use 80.
Update Python style guide to 2.59:
- Add more examples of bad code to the default arguments section.
- Allow ''' when ' is used as the single quote within a file.
- Remove references to pychecker. Recommend pylint.
- Add more examples to the indentation section.
Update JavaScript style guide to 2.93:
- Add @nocompile.
- Fix a few typos.
- When wrapping lines, indent more deeply for child expressions.
- Document that @const can be used on a constructor.
- Update eval section to discourage using eval for RPC.
- Update an example to avoid encouraging using numbers as booleans.
- Allow for no indentation of @desc jsdoc tags.
- Add @public discussion.
Update shell style guide to 1.26:
- Add a section on style for case statements.
Update Common Lisp style guide to 1.23:
- fare-matcher was superseded by optima.
- Clarify wording regarding DYNAMIC-EXTENT.
- Add boost::bimap to the list of allowed Boost libraries.
- C++11: remove mention of constexpr.
- Remove noun/verb naming rules, and consolidate "General Naming Rules".
- C++11: allow variadic templates.
- Revise guidance on function definition comments.
- Clarify that one space is sufficient before trailing /* */ comments.
- C++11: allow alias templates.
- C++11: allow <array>, deprecate Boost array.
- C++11: allow unique_ptr, deprecate Boost pointer container.
- C++11: allow braced initializer lists.
Update Objective-C style guide to 2.56:
- Add details on constant declarations to clarify naming and scope issues.
- Update link to Apple's Objective-C guide.
- Allow left-aligning multi-block method invocation segments.
- Add section on container literals.
Update Python style guide to 2.54:
- Allow str.format in addition to the % operator.
- Allow #!/usr/bin/python2 and #!/usr/bin/python3.
- Move the closing brace example from column 4 to 0.
- Remove the requirement to use named parameters for arguments with defaults.
Update HTML/CSS style guide to 2.23:
- No changes.
Update JavaScript style guide to 2.82:
- Fix typos, whitespace, and character entities.
- Include property descriptions in the clause about omitting obvious comments.
- Make file overviews optional.
- Fix example in "HTML in JSDoc" section.
- Remove the semicolon-insertion language from the operators section.
- State that complete sentences are recommended but not required.
- Document usage of goog.scope to declare new classes.
Update Common Lisp style guide to 1.20:
- Indicate both variable and function predicates require a "p".
- Make the abbreviations rules consistent and in one location.
- Don't allow for the use of &AUX.
- Allow for "body" and "end" as exceptions to the suffix rule.
- Use the TODO convention to mark code that needs to be addressed.
- Remove file maintainership requirements, require a description.
- Change top-level form requirements to the length of a page.
- Remove "don't be clever".
- 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.
- 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.
- 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 '&'.
- 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.
- 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.
- 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.
- Add leading blank line exception.
- Improve guidance for function definition comments.
- Tweak class comment example to not violate type naming guidelines.
Update Objective-C style guide to 2.21:
- Prohibit +new.
Update JavaScript style guide to 2.9:
- Add new "Function Declarations Within Blocks" section.
- Add new "Internet Explorer's Conditional Comments" section.
- Add new "Alias long type names to improve readability" section.
- Add @lends.
- Allow overloading a function judiciously.
- _unittest and _regtest are deprecated.
- Document C++0x policy.
- Allow namespace aliases in .h files when inside namespaces.
- Give examples for and against parentheses with return.
- Update set of allowed Boost headers.
- Add a caveat to the forward-declaration section, mentioning impicit
constructors.
- Forbid the use of operator synonyms such as "and."
- Specify the naming convention (OrDie) to use when a function has
crash-on-failure semantics.
- Allow static const data members to be non-private.
- Specify placement of friend declarations.
- Require each file to include headers that they use.
Update Objective-C style guide to 2.18:
- Prefer @optional to informal protocols when possible.
- Specify formatting for invoking methods.
- Require that -dealloc be easy to review.
- 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.
- 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.
- Clarify that a "very strong convention" is, in fact, only very strong
within Google code
- Update the style guide with an additional naming possibility for enums:
kEnumName
- Reword the summary for the section on header file dependencies
- Simplify wording regarding static variables
Update Objective-C style guide to 2.11:
- Provide guidance on when to use #import and #include
- Display revision in style guide
Update styleguide.xsl with a hint of things to come
Set svn:eol-style on xmlstyle.html
- Allow unsigned types where defined overflow behavior is desired
- Clarify that a function-closing } is permitted on the same line as an
opening { for one-line functions
Set svn:eol-style = native on google-c-style.el
- Change list of permitted Boost libraries
- Permit one space before // in a new {scope}
- Grammar fix!
Update Objective-C style guide:
- Link spacing changes only
Ted Osborne
Google Python team
mark@chromium.org
mmentovai
erg@google.com