'can' operator?

pg has asked for the wisdom of the Perl Monks concerning the following question:

I was wondering about something. I can check whether a class has a certain method, by calling can, for example,

use Math::Complex;
print "plus is supported\n" if (Math::Complex->can("plus"));
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It works. I checked the Math::Complex module, the overloaded “+” actually calls this 'plus' function. Now, is it not normal for me to expect that, the following should work?

use Math::Complex;
print "+ is supported\n" if (Math::Complex->can("+"));
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But it does not, even though “+” is overloaded for this class. My question is:

Did I do something wrong? If yes, then what is the correct syntax to check whether an operator is overloaded?
If I didn’t do anything wrong, is it not nice for Perl to support a unified interface for checking whether a method, or operator is supported? They are both operations you can apply on a class/object though. Also, you remember those operators by their symbols, for example "+", not by the methods under, for example, if I didn't check the Complex.pm, how can I know that "+" is actually "plus"?

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Re: 'can' operator? by broquaint (Abbot) on Nov 18, 2002 at 18:14 UTC
Did I do something wrong? If yes, then what is the correct syntax to check whether an operator is overloaded? Yes, `can` only checks whether a given class/object implements a method, not whether operators overloaded. For that you'll want `overload::Method` from the `overload` module. HTH `_________ broquaint`	[reply]
Re: 'can' operator? by Zaxo (Archbishop) on Nov 18, 2002 at 20:33 UTC
The overload pragmatic provides a couple of functions you can use for that. `overload::Overloaded('$foo+1')` takes a perl expression as a string and tells you whether any of its operators are overloaded in the context of that expression. `overload::Method($obj,'+')` returns a code reference to the method overloading '+' for $obj, or undef if not overloaded. After Compline, Zaxo	[reply]