The CodeHilite Extension adds code/syntax highlighting to standard Python-Markdown code blocks using Pygments.
This extension is included in the Markdown library.
You will also need to download and install the Pygments package on your
PYTHONPATH
. You will need to determine the appropriate CSS classes and create
appropriate rules for them, which are either defined in or linked from the
header of your HTML templates. See the excellent documentation for more
details. If no language is defined, Pygments will attempt to guess the
language. When that fails, the code block will display as un-highlighted code.
Note
The css and/or javascript is not included as part of this extension but shall always be provided by the end user.
The CodeHilite Extension follows the same syntax as regular Markdown code blocks, with one exception. The hiliter needs to know what language to use for the code block. There are three ways to tell the hiliter what language the code block contains and each one has a different result.
Note
The format of the language identifier only effects the display of line numbers
if linenums
is set to None
(the default). If set to True
or False
(see Usage below) the format of the identifier has no effect on the
display of line numbers -- it only serves as a means to define the language
of the code block.
If the first line of the codeblock contains a shebang, the language is derived from that and line numbers are used.
#!/usr/bin/python
# Code goes here ...
Will result in:
#!/usr/bin/python
# Code goes here ...
If the first line contains a shebang, but the shebang line does not contain a
path (a single /
or even a space), then that line is removed from the code
block before processing. Line numbers are used.
#!python
# Code goes here ...
Will result in:
# Code goes here ...
If the first line begins with three or more colons, the text following the colons identifies the language. The first line is removed from the code block before processing and line numbers are not used.
:::python
# Code goes here ...
Will result in:
# Code goes here ...
CodeHilite is completely backward compatible so that if a code block is
encountered that does not define a language, the block is simply wrapped in
<pre>
tags and output.
# Code goes here ...
Will result in:
# Code goes here ...
Lets see the source for that:
<div class="codehilite"><pre><code># Code goes here ...
</code></pre></div>
Note
When no language is defined, the Pygments highlighting engine will try to guess
the language (unless guess_lang
is set to False
). Upon failure, the same
behavior will happen as described above.
From the Python interpreter:
>>> html = markdown.markdown(text, extensions=['codehilite'])
If you want to force every code block to have line numbers, even when using
colons (:::
) for language identification, set linenums
to True
.
>>> html = markdown.markdown(text,
... extensions=['codehilite(linenums=True)']
... )
If you do not want any code block to have line numbers, even when using
SheBangs (#!
) for language identification, set linenums
to False
.
>>> html = markdown.markdown(text,
... extensions=['codehilite(linenums=False)']
... )
If you want to prevent Pygments from guessing the language, only highlighting
blocks when you explicitly request it, set the guess_lang
setting to False
.
>>> html = markdown.markdown(text,
... extensions=['codehilite(guess_lang=False)']
... )