The reason that using references as hash keys are bad is
that the references are 'Stringified' in the hash thus:

my $val = 1;
my %hash = ( \$val => 2 );
foreach my $ref (keys %hash)
{
    print $$ref, "\n";
}

[download]

Does not yield the value 1, instead you get undef.

In reply to Re: Re: Given ref to hash value, retrieve the key by linux454
in thread Given ref to hash value, retrieve the key by gazpacho

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