mirror of
https://github.com/showdownjs/showdown.git
synced 2024-03-22 13:30:55 +08:00
194 lines
5.6 KiB
Markdown
194 lines
5.6 KiB
Markdown
|
|
NOTE -- Showdown on GitHub
|
|
==========================
|
|
|
|
Please note that I, Corey, am not the author of Showdown. Rather, I found it
|
|
some time back at <http://attacklab.net/showdown/> and wanted to see it
|
|
available on GitHub.
|
|
|
|
All credit and praise for authoring this library should go to John Fraser.
|
|
|
|
Oh, and John Gruber of course.
|
|
|
|
That said, I have recently see some GitHub forking activity and a pull
|
|
request. As such, I will endeavor to ordain myself as a maintainer of
|
|
Showdown, at least as it exists on GitHub.
|
|
|
|
Apologies for any confusion or perceived misinformation.
|
|
|
|
Cheers,
|
|
Corey
|
|
|
|
|
|
Showdown -- A JavaScript port of Markdown
|
|
=========================================
|
|
|
|
Showdown Copyright (c) 2007 John Fraser.
|
|
<http://www.attacklab.net/>
|
|
|
|
Original Markdown Copyright (c) 2004-2005 John Gruber
|
|
<http://daringfireball.net/projects/markdown/>
|
|
|
|
Redistributable under a BSD-style open source license.
|
|
See license.txt for more information.
|
|
|
|
|
|
What's it for?
|
|
--------------
|
|
|
|
Developers can use Showdown to:
|
|
|
|
* Add in-browser preview to existing Markdown apps
|
|
|
|
Showdown's output is (almost always) identical to
|
|
markdown.pl's, so the server can reproduce exactly
|
|
the output that the user saw. (See below for
|
|
exceptions.)
|
|
|
|
* Add Markdown input to programs that don't support it
|
|
|
|
Any app that accepts HTML input can now be made to speak
|
|
Markdown by modifying the input pages's HTML. If your
|
|
application lets users edit documents again later,
|
|
then they won't have access to the original Markdown
|
|
text. But this should be good enough for many
|
|
uses -- and you can do it with just a two-line
|
|
`onsubmit` function!
|
|
|
|
* Add Markdown input to closed-source web apps
|
|
|
|
You can write bookmarklets or userscripts to extend
|
|
any standard textarea on the web so that it accepts
|
|
Markdown instead of HTML. With a little more hacking,
|
|
the same can probably be done with many rich edit
|
|
controls.
|
|
|
|
* Build new web apps from scratch
|
|
|
|
A Showdown front-end can send back text in Markdown,
|
|
HTML or both, so you can trade bandwidth for server
|
|
load to reduce your cost of operation. If your app
|
|
requires JavaScript, you won't need to do any
|
|
Markdown processing on the server at all. (For most
|
|
uses, you'll still need to sanitize the HTML before
|
|
showing it to other users -- but you'd need to do
|
|
that anyway if you're allowing raw HTML in your
|
|
Markdown.)
|
|
|
|
|
|
Browser Compatibility
|
|
---------------------
|
|
|
|
Showdown has been tested successfully with:
|
|
|
|
- Firefox 1.5 and 2.0
|
|
- Internet Explorer 6 and 7
|
|
- Safari 2.0.4
|
|
- Opera 8.54 and 9.10
|
|
- Netscape 8.1.2
|
|
- Konqueror 3.5.4
|
|
|
|
In theory, Showdown will work in any browser that supports ECMA 262 3rd Edition (JavaScript 1.5). The converter itself might even work in things that aren't web browsers, like Acrobat. No promises.
|
|
|
|
|
|
Known Differences in Output
|
|
---------------------------
|
|
|
|
In most cases, Showdown's output is identical to that of Perl Markdown v1.0.2b7. What follows is a list of all known deviations. Please email me if you find more.
|
|
|
|
|
|
* This release uses the HTML parser from Markdown 1.0.2b2,
|
|
which means it fails `Inline HTML (Advanced).text` from
|
|
the Markdown test suite:
|
|
|
|
<div>
|
|
<div>
|
|
unindented == broken
|
|
</div>
|
|
</div>
|
|
|
|
|
|
* Showdown doesn't support the markdown="1" attribute:
|
|
|
|
<div markdown="1">
|
|
Markdown does *not* work in here.
|
|
</div>
|
|
|
|
This is half laziness on my part and half stubbornness.
|
|
Markdown is smart enough to process the contents of span-
|
|
level tags without screwing things up; shouldn't it be
|
|
able to do the same inside block elements? Let's find a
|
|
way to make markdown="1" the default.
|
|
|
|
|
|
* You can only nest square brackets in link titles to a
|
|
depth of two levels:
|
|
|
|
[[fine]](http://www.attacklab.net/)
|
|
[[[broken]]](http://www.attacklab.net/)
|
|
|
|
If you need more, you can escape them with backslashes.
|
|
|
|
|
|
* When sublists have paragraphs, Showdown produces equivalent
|
|
HTML with a slightly different arrangement of newlines:
|
|
|
|
+ item
|
|
|
|
- subitem
|
|
|
|
The HTML has a superfluous newline before this
|
|
paragraph.
|
|
|
|
- subitem
|
|
|
|
The HTML here is unchanged.
|
|
|
|
- subitem
|
|
|
|
The HTML is missing a newline after this
|
|
list subitem.
|
|
|
|
|
|
|
|
* Markdown.pl creates empty title attributes for
|
|
inline-style images:
|
|
|
|
Here's an empty title on an inline-style
|
|
![image](http://w3.org/Icons/valid-xhtml10).
|
|
|
|
I tried to replicate this to clean up my diffs during
|
|
testing, but I went too far: now Showdown also makes
|
|
empty titles for reference-style images:
|
|
|
|
Showdown makes an empty title for
|
|
reference-style ![images][] too.
|
|
|
|
[images]: http://w3.org/Icons/valid-xhtml10
|
|
|
|
|
|
* With crazy input, Markdown will mistakenly put
|
|
`<strong>` or `<em>` tags in URLs:
|
|
|
|
<a href="<*Markdown adds em tags in here*>">
|
|
improbable URL
|
|
</a>
|
|
|
|
Showdown won't. But still, don't do that.
|
|
|
|
|
|
Credits
|
|
---------------------------
|
|
|
|
* Origins
|
|
* [John Fraser](http://http://attacklab.net/):
|
|
Author of Showdown
|
|
* [John Gruber](http://daringfireball.net/projects/markdown/):
|
|
Author of Markdown
|
|
* Maintenance
|
|
* [Corey Innis](http://github.com/coreyti):
|
|
GitHub project maintainer
|
|
* [Remy Sharp](http://remysharp.com/):
|
|
CommonJS-compatibility and more
|
|
|