package My::TieHashTest;
require Tie::Hash;
@ISA= ( Tie::StdHash );

for( qw/ TIEHASH STORE FETCH FIRSTKEY NEXTKEY 
	EXISTS CLEAR DELETE UNTIE DESTROY / )
{	
	eval qq{ 
		sub $_ 
		{ 
			notify($_); 
			shift->SUPER::$_ 
		}
	}
}

sub notify { warn shift, $/ }


package main;
use strict;
use warnings;

tie my %hash => 'My::TieHashTest'
	or die;

%hash= ( a=>1, b=>2, c=>3 );
$hash{d}= 4;

print $_,$/ for keys %hash;

##</code><code>##

> t-tiehash.pl
TIEHASH
CLEAR
STORE
STORE
STORE
STORE
FIRSTKEY
NEXTKEY

DESTROY