MaplePrimes - comments on Post, Understanding ::uneval

MaplePrimes - comments on Post, Understanding ::uneval http://www.mapleprimes.com/posts/97555-Understanding-uneval en-us 2026 Maplesoft, A Division of Waterloo Maple Inc. Maplesoft Document System Wed, 10 Jun 2026 20:49:41 GMT Wed, 10 Jun 2026 20:49:41 GMT The latest comments added to the Post, Understanding ::uneval http://www.mapleprimes.com/images/mapleprimeswhite.jpg MaplePrimes - comments on Post, Understanding ::uneval http://www.mapleprimes.com/posts/97555-Understanding-uneval simple useful example http://www.mapleprimes.com/posts/97555-Understanding-uneval?ref=Feed:MaplePrimes:Understanding ::uneval:Comments#comment97577 For people like me who are not among that ~10 in the world, the example on the help page doesn't really give a good idea of why you might want to use ::uneval. When I use it, it is mostly for testing or measuring the evaluation of expressions. So, for those people who might end up here, here is a small example: <pre> benchmark := proc(e::uneval) local t, b; t, b := time(), kernelopts(':-bytesused'); eval(e); return (time() - t)*Unit(second), (kernelopts(':-bytesused') - b)*Unit(byte); end proc</pre> This is a simple extention of <a href="http://www.maplesoft.com/support/help/search.aspx?term=time">?time</a> that also records the memory used to evaluate the expression 'e'. <pre>(**) benchmark(solve(x^50-1)); 0.201 [s], 10924456 [byte] </pre> The latest comments added to the Post, Understanding ::uneval 97577 Thu, 07 Oct 2010 19:54:41 Z John May John May Sigh http://www.mapleprimes.com/posts/97555-Understanding-uneval?ref=Feed:MaplePrimes:Understanding ::uneval:Comments#comment97625 <a href="http://www.mapleprimes.com/posts/97555-Understanding-uneval#comment97577">@John May</a> I was rather hoping to count you amongst those few people!  Thanks for the useful example. Of course, there are some subtle differences between an explicit call to 'eval' and the (implicit) full-eval which happens from Maple's top-level, so even your simple example will not quite 'work', for that vast hinterland that is the obscure corner cases of Maple's evaluation rules.  The latest comments added to the Post, Understanding ::uneval 97625 Fri, 08 Oct 2010 18:56:20 Z JacquesC JacquesC subtle differences http://www.mapleprimes.com/posts/97555-Understanding-uneval?ref=Feed:MaplePrimes:Understanding ::uneval:Comments#comment97640 <a href="http://www.mapleprimes.com/posts/97555-Understanding-uneval#comment97625">@JacquesC</a> I wonder also whether there are "subtle differences" between using the uneval modifier on the parameter and using unevaluation quotes ('...') on the argument. If so, which ones? The latest comments added to the Post, Understanding ::uneval 97640 Fri, 08 Oct 2010 23:31:28 Z Alejandro Jakubi Alejandro Jakubi @JacquesC Not to imply that I am disinterested.  http://www.mapleprimes.com/posts/97555-Understanding-uneval?ref=Feed:MaplePrimes:Understanding ::uneval:Comments#comment97643 <a href="http://www.mapleprimes.com/posts/97555-Understanding-uneval#comment97625">@JacquesC</a> Not to imply that I am disinterested.  I just can imagine myself being in the top 10. The latest comments added to the Post, Understanding ::uneval 97643 Sat, 09 Oct 2010 00:29:25 Z John May John May Another example? http://www.mapleprimes.com/posts/97555-Understanding-uneval?ref=Feed:MaplePrimes:Understanding ::uneval:Comments#comment97763 I'm certainly not among the 10 people.  Below is how I examine the "internal" structure of int(x,x) before int(x,x) gets evaluated: > mydismantle := proc(expr::uneval) dismantle(expr); end proc: > dismantle(int(x,x)); SUM(3)    PROD(3)       NAME(4): x       INTPOS(2): 2    RATIONAL(3): 1/2       INTPOS(2): 1       INTPOS(2): 2 > mydismantle(int(x,x)); FUNCTION(3)    NAME(4): int #[protected, _syslib]    EXPSEQ(3)       NAME(4): x       NAME(4): x > The latest comments added to the Post, Understanding ::uneval 97763 Wed, 13 Oct 2010 19:38:36 Z Clare So Clare So Yes, exactly http://www.mapleprimes.com/posts/97555-Understanding-uneval?ref=Feed:MaplePrimes:Understanding ::uneval:Comments#comment97764 <a href="http://www.mapleprimes.com/posts/97555-Understanding-uneval#comment97763">@Clare So</a> that is the kind of example I had in mind.  For example, this is how Maple's ContextMenu has to work.  It's tricky, because it can get inputs which would never be seen as output, so the analysis of such expression is rather tricky. The latest comments added to the Post, Understanding ::uneval 97764 Wed, 13 Oct 2010 19:56:49 Z JacquesC JacquesC