http://dev.clojure.org/jira This file is an XML representation of an issue en-us 4.4 649 25-07-2011 http://dev.clojure.org/jira/browse/CLJS-471 ClojureScript <p>An empty regexp of the form <tt>#""</tt> compiles to <tt>//</tt>, which is not an empty regexp but a comment, causing the code following the supposed regexp on the affected line to be commented out. This tends to cause compiler errors when Closure Compiler tries to parse it.</p> <p><tt>#""</tt> should instead produce either <tt>/(?:&#41;/</tt> or <tt>new RegExp("")</tt>.</p> CLJS-471

Empty regexp causes Closure Compiler error

Defect Trivial Open Unresolved Michał Marczyk Bodil Stokke Wed, 13 Feb 2013 15:33:55 -0600 Thu, 25 Apr 2013 05:57:34 -0500 0 1 <p>Commit message:</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre>CLJS-471: prevent empty regexps from causing compiler errors This patch chooses to emit (new RegExp("")) rather than /(?:)/ so that (pr-str #"") returns "#\"\"" rather than "#\"(?:)\"" A test for the above is included. </pre> </div></div> <p>I tried applying this in master, the included test fails.</p> <p>Thanks for letting me know. I've checked the value of <tt>new RegExp("").source</tt> in a Node.js REPL (0.10.3) and it turns out to be <tt>'(?<img class="emoticon" src="http://dev.clojure.org/jira/images/icons/emoticons/smile.gif" height="20" width="20" align="absmiddle" alt="" border="0"/>'</tt>. So, how important is it that we return <tt>"#\"\""</tt> rather than <tt>"#\"(?<img class="emoticon" src="http://dev.clojure.org/jira/images/icons/emoticons/smile.gif" height="20" width="20" align="absmiddle" alt="" border="0"/>\""</tt> anyway? I'm thinking maybe not that much, seeing how regexp support in JS is different to that on the JVM in more fundamental ways. I'll just assume this is correct and attach a new patch accepting both representations soon. Of course if there's a better way to do it, I'll be happy to implement it.</p> Global Rank