Dear Monks,

What's the most efficient way to create and reference a key only hash (In general, but specifically in a mod-perl environment)? Is it: 

#!/usr/bin/perl -w
use strict;

my %hash1 = (
    shave  => '',
    the    => '',
    modern => '',
    way    => '',
);

my %hash2 = (
    shave  => 1,
    the    => 1,
    modern => 1,
    way    => 1,
);

my $word   = 'modern';

if( exists($hash1{$word}) ) {
    print "Word $word is in hash1\n";
    }
if( $hash2{$word} ) {
    print "Word $word is in hash2\n";
    }

[download]
I am aware of  perl is a profligate wastrel when it comes to memory use. But the -DL and warn(!!!) hacks don't work on my Perl v5.8.8. I don't get any memory debugging with: 
export PERL_DEBUG_MSTATS=1
perl test_hasheffeciency.pl

[download]

In reply to Effecicncy of key-only hash by brycen

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