Just my two cents: 
sub foo { }

foreach (qw[ foo bar ])
{
        print "$_? ",(defined(*$_{CODE})? "defined":"undef"), "\n";
}

[download]
Using this kind of test, you can check for other stuff, like GLOB, filehandles and such, which aren't easily prefixed with something like '$', '&', '%' or '@'.

In reply to Re: Test for Subroutine Definition by tadman
in thread test for subroutine existence by twerq

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