&gt; This defines a named capture group, &lt;m&gt;.<p>I thought JavaScript regexes don&#x27;t support named capturing groups. Is Atom using some library or custom functionality for that?<p>EDIT: Or is it a CoffeeScript addition? In their table of contents I only see regex blocks mentioned though (<a href="http:&#x2F;&#x2F;coffeescript.org&#x2F;#regexes" rel="nofollow">http:&#x2F;&#x2F;coffeescript.org&#x2F;#regexes</a>).