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/CLJ-1136 Clojure <p>Type hints don't work as expected in binding forms. </p> <p>The following form results in a reflection warning:</p> <p> (let [^{:tag (Class/forName "<span class="error">&#91;Ljava.lang.Object;&quot;)} a (make-array Object 2)&#93;</span><br/> (aget a 0))</p> <p>However, hinting does appear to work correctly on vars:</p> <p> (def ^{:tag (Class/forName "[Ljava.lang.Object;")} a (make-array Object 2))<br/> (aget a 0) ;; no reflection warning</p> replicated on OpenJDK 7u9 on Ubuntu 12.04, and Hotspot 1.6.0_37 on OSX Lion CLJ-1136

Type hinting for array classes does not work in binding forms

Defect Major Open Unresolved Unassigned Luke VanderHart Compiler bug Thu, 20 Dec 2012 14:59:58 -0600 Fri, 21 Dec 2012 11:09:56 -0600 Release 1.4 Release 1.5 0 0 <p>It's a little more insidious than type hinting: the compiler doesn't evaluate metadata in the binding vec.</p> <p>This doesn't throw the necessary exception...</p> <p>(let <span class="error">&#91;^{:foo (Class/forName &quot;not real&quot;)} bar 42&#93;</span><br/> bar)</p> <p>neither this...</p> <p>(let <span class="error">&#91;^{gyorgy ligeti} a 42&#93;</span><br/> a)</p> <p>Gyorgy Ligeti never resolves.</p> <p>These two equivalent examples don't reflect: <br/> (let <span class="error">&#91;^objects a (make-array Object 2)&#93;</span><br/> (aget a 0))</p> <p>(let <span class="error">&#91;a ^objects (make-array Object 2)&#93;</span><br/> (aget a 0))</p> <p>On only the left-hand side of a local binding, metadata on a symbol is not analyzed or evaluated.</p> Global Rank