Re^2: How come undef eq '' ??

in reply to Re: How come undef eq '' ??
in thread How come undef eq '' ??

Is there a more graceful way of doing this other than disabling warnings for that chunk - through __WARN__ - as I have done there?

I think your introduction of _unset_sig_warn() was misguided. Why not simply use lexical warnings? (see: perllexwarn). You typically switch off specific warnings in the smallest possible lexical scope. For example:

use strict;
use warnings;
my $z;    # $z contains undef
if ($z eq "") {    # oops, Use of uninitialized value $z in string eq
    print "1. string is empty (with warnings)\n";
}
# Switch off the specific uninitialized warning in a lexical scope.
{
    no warnings 'uninitialized';
    if ($z eq "") {    # no warning this time
        print "2. string is empty (with no warnings)\n";
    }
}
# warnings switched back on at end of scope
[download]

If there is a reason you cannot use this technique in your inherited CPAN module please let us know.

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Re^3: How come undef eq '' ?? by tmharish (Friar) on Jan 30, 2013 at 19:43 UTC
lexical warnings - perfect! Appreciate you taking the time to go through the code. Thank you!	[reply]

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