How do I set an HTML class attribute in Markdown?
Markdown Extra supports class and id attributes using curly braces. See: https://michelf.ca/projects/php-markdown/extra/#spe-attr
Markdown has an extension (attr_list.py) which allows you to use Maruku's {: .classname}
syntax.
Though not answering the question exactly. You can use a different render too like Maruku or Kramdown:
## My Title
A paragraph of content here.
~~~
code_line(1);
// a code comment
class MoreCode { }
~~~
{: .prettyprint}
and more text to follow...
Output (tested with haml & kramdown):
<pre class="prettyprint"><code>
code_line(1);
// a code comment
class MoreCode { }
</code></pre>
Kramdown syntax: http://kramdown.rubyforge.org/quickref.html#block-attributes
You can embed HTML in Markdown. Type literally what you want, with no indent.
<code class="prettyprint">
code_line(1);
// a code comment
class More Code { }
</code>
For the specific case of syntax highlighting following the back ticks at the start of a fenced code block with the language works just about everywhere these days.
```js
code_line(1);
// a code comment
class MoreCode { }
```