showdownjs/test/cases/github-style-codeblock.html

<p>Define a function in javascript:</p>
<pre><code>function MyFunc(a) {
  var s = '`';
  }
</code></pre>
<p>And some HTML</p>
<pre><code class="html language-html">&lt;div&gt;HTML!&lt;/div&gt;
</code></pre>
<p>Use more than 3 backticks</p>
<pre><code>some code
</code></pre>
<p>Use tilde as delimiter</p>
<pre><code>another piece of code
</code></pre>