Perhaps it's that high so that it never "dies"? And the reason it doesn't say undef is constant (from my function) is because undef = $foo is illegal, but (undef) = $foo isn't. Fix: 
sub is_const { defined($_[0]) and !eval { ($_[0]) = $_[0]; 1 } }

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japhy -- Perl and Regex Hacker

In reply to Re: Re: Re: Re: Detecting constant arguments passed to subroutines by japhy
in thread Detecting constant arguments passed to subroutines by dcd

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