I was a little surprised to find out: 
use strict;
my $self = {};
my $f1  = "aaa";
my $f2  = "bbb";
my $f3  = "ccc";
my $val = "val";

print "count = ".%$self."\n";
print "found\n"  if exists $self->{$f1}{$f2}{$f3};
print "count = ".%$self."\n";

print "it is aaa\n" if exists $self->{$f1};
print "it is bbb\n" if exists $self->{$f1}{$f2};
print "it is ccc\n" if exists $self->{$f1}{$f2}{$f3};

print "count = ".%$self."\n";

[download]
That the exists key word is "creating" the hash...

Do I really need to test each one (left to right)?

Argh

Fixed code tags - dvergin 2002-07-03

In reply to hash surprise by smackdab

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