Help to understand following javascript code
<p>Does anyone know what language is it in the following code snippet</p>

<pre><code>&lt;div style="margin: 4px 4px 4px 4px; padding: 4px; background-color: #eeeeee;" class="small bold"&gt;

                &lt;a href="javascript:openDetails('[[versionVID]]');"&gt;Details&lt;/a&gt;
                [[is_real=
                &lt;span style="margin-left: 4px;"&gt;&lt;a href="javascript:viewFileX('[[file_x]]',  '[[project]]', '[[version]]','[[user]]');"&gt;View File&lt;/a&gt;&lt;/span&gt;
                ]]
&lt;/div&gt;
</code></pre>

<p>I understand HTML part but unable to understand syntax with multiple square brackets with some variable name between</p>
