| Tie::RefHash(3perl) - phpMan
Tie::RefHash(3perl) Perl Programmers Reference Guide Tie::RefHash(3perl)
NAME
Tie::RefHash - use references as hash keys
SYNOPSIS
require 5.004;
use Tie::RefHash;
tie HASHVARIABLE, 'Tie::RefHash', LIST;
tie HASHVARIABLE, 'Tie::RefHash::Nestable', LIST;
untie HASHVARIABLE;
DESCRIPTION
This module provides the ability to use references as hash keys if you first "tie" the
hash variable to this module. Normally, only the keys of the tied hash itself are
preserved as references; to use references as keys in hashes-of-hashes, use
Tie::RefHash::Nestable, included as part of Tie::RefHash.
It is implemented using the standard perl TIEHASH interface. Please see the "tie" entry
in perlfunc(1) and perltie(1) for more information.
The Nestable version works by looking for hash references being stored and converting them
to tied hashes so that they too can have references as keys. This will happen without
warning whenever you store a reference to one of your own hashes in the tied hash.
EXAMPLE
use Tie::RefHash;
tie %h, 'Tie::RefHash';
$a = [];
$b = {};
$c = \*main;
$d = \"gunk";
$e = sub { 'foo' };
%h = ($a => 1, $b => 2, $c => 3, $d => 4, $e => 5);
$a->[0] = 'foo';
$b->{foo} = 'bar';
for (keys %h) {
print ref($_), "\n";
}
tie %h, 'Tie::RefHash::Nestable';
$h{$a}->{$b} = 1;
for (keys %h, keys %{$h{$a}}) {
print ref($_), "\n";
}
THREAD SUPPORT
Tie::RefHash fully supports threading using the "CLONE" method.
STORABLE SUPPORT
Storable hooks are provided for semantically correct serialization and cloning of tied
refhashes.
RELIC SUPPORT
This version of Tie::RefHash seems to no longer work with 5.004. This has not been
throughly investigated. Patches welcome ;-)
LICENSE
This program is free software; you can redistribute it and/or modify it under the same
terms as Perl itself
MAINTAINER
Yuval Kogman <nothingmuch AT woobling.org>
AUTHOR
Gurusamy Sarathy gsar AT activestate.com
'Nestable' by Ed Avis ed AT membled.com
SEE ALSO
perl(1), perlfunc(1), perltie(1)
perl v5.20.2 2014-12-27 Tie::RefHash(3perl)
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