> that autovivication doesn't happen when you simply check wether a hash key exists or is true.

unfortunately not that simple!

use strict;   # or die
use warnings; # or die
 
my %hash = (
   cogito   => "ergo sum"   # I think, so I exist
);
 
if (exists $hash{absum}{absum}) {
    print "Absum exists.";
} else {
    print "Absum doesn't exist.\n";
    # which would explain it's name...
}
 
print "Keys in the hash: ", join(" :: ", keys %hash), "\n";

[download]
output 
/usr/bin/perl -w /home/lanx/tst.pl 
Absum doesn't exist.
Keys in the hash: cogito :: absum

[download]

Cheers Rolf

In reply to Re^2: Best Hash Practices? by LanX
in thread Best Hash Practices? by DamianKaelGreen

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