http://www.perlmonks.org?node_id=1268

Tie::RefHash

See the current Perl documentation for Tie::RefHash.

Here is our local, out-dated (pre-5.6) version:

Tie::RefHash - use references as hash keys

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    require 5.004;
    use Tie::RefHash;
    tie HASHVARIABLE, 'Tie::RefHash', LIST;

    untie HASHVARIABLE;

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This module provides the ability to use references as hash keys if you first tie the hash variable to this module.

It is implemented using the standard perl TIEHASH interface. Please see the tie entry in perlfunc(1) and perltie(1) for more information.

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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";
    }

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AUTHOR

Gurusamy Sarathy gsar@umich.edu

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VERSION

Version 1.2 15 Dec 1996

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SEE ALSO

perl(1), perlfunc(1), perltie(1)

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