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<p class="p1">On 2013-12-04 03:23:59 +0000, bearophile said:</p>
<p class="p2"><br></p>
<p class="p3">Joshua Niehus:</p>
<p class="p4"><br></p>
<p class="p5">This would make for a good blog post/wiki article.<span class="Apple-converted-space"> </span>Does one already exist?</p>
<p class="p6"><br></p>
<p class="p7">If you have a AST macros like in Julia language, I think you can write something like:</p>
<p class="p6"><br></p>
<p class="p7">@setExpr(a <span class="s1">∪</span> (b <span class="s1">∩</span> c));</p>
<p class="p6"><br></p>
<p class="p7">The main difference is that the compiler gives you a tree in the macro to work on, instead of a string to parse and munge.</p>
<p class="p6"><br></p>
<p class="p7">Bye,</p>
<p class="p7">bearophile</p>
<p class="p8"><br></p>
<p class="p9">Can't you define</p>
<p class="p10"><br></p>
<p class="p11">template <span class="s2">setExpr</span>(string expr)</p>
<p class="p11">{</p>
<p class="p11"><span class="Apple-tab-span"> </span>PeggedStuff...</p>
<p class="p10"><br></p>
<p class="p11"><span class="Apple-tab-span"> </span>mixin(PeggedStuff());</p>
<p class="p11">}</p>
<p class="p10"><br></p>
<p class="p12"><span class="s3">setExpr!(q{</span>a <span class="s1">∪</span> (b <span class="s1">∩</span> c)});<span class="s3"> ?</span></p>
<p class="p10"><br></p>
<p class="p11">-Shammah</p>
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