However be careful with exists(), it creates stuff for you:

use Data::Dumper;

use strict;
use warnings;

my $h = {};
if (exists($h->{"a"}{"b"})) {
}
if (exists($h->{"a"})) {
    print "exists\n";
}
print Dumper($h);

[download]

This will make $h->{"a"} exists.

In reply to Re^4: Syntax for Hashes of Hashes by pg
in thread Syntax for Hashes of Hashes by o2bwise

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