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NAME
    Class::PseudoHash - Emulates Pseudo-Hash behaviour via overload

VERSION
    This document describes version 1.10 of Class::PseudoHash, released
    October 14, 2007.

SYNOPSIS
        use Class::PseudoHash;

        my @args = ([qw/key1 key2 key3 key4/], [1..10]);
        my $ref1 = fields::phash(@args);            # phash() override
        my $ref2 = Class::PseudoHash->new(@args);   # constructor syntax

DESCRIPTION
    Due to its impact on overall performance of ordinary hashes,
    pseudo-hashes are deprecated in Perl 5.8.

    As of Perl 5.10, pseudo-hashes have been removed from Perl, replaced by
    restricted hashes provided by Hash::Util. Additionally, Perl 5.10 no
    longer supports the "fields::phash()" API.

    Although "Pseudo-hashes: Using an array as a hash" in perlref recommends
    against depending on the underlying implementation (i.e. using the first
    array element as hash indice), there are undoubtly many legacy codebase
    still depending on pseudohashes; elimination of pseudo-hashes would
    therefore require a massive rewrite of their programs.

    Back in 2002, as one of the primary victims, I tried to devise a drop-in
    solution that could emulate exactly the same semantic of pseudo-hashes,
    thus keeping all my legacy code intact. So "Class::PseudoHash" was born.

    Hence, if your code use the preferred "fields::phash()" function, just
    write:

        use fields;
        use Class::PseudoHash;

    then everything will work like before. If you are creating pseudo-hashes
    by hand ("[{}]" anyone?), just write this instead:

        $ref = Class::PseudoHash->new;

    and use the returned object in whatever way you like.

NOTES
    If you set $Class::PseudoHash::FixedKeys to a false value and tries to
    access a non-existent hash key, then a new pseudo-hash entry will be
    created silently. This is most useful if you're already using untyped
    pseudo-hashes, and don't want the compile-time checking feature.

    Compile-time validating of keys is not possible with this module, for
    obvious reasons. Also, the performance will not be as fast as typed
    pseudo-hashes (but generally faster than untyped ones).

SEE ALSO
    fields, "Pseudo-hashes: Using an array as a hash" in perlref

AUTHORS
    Audrey Tang <cpan@audreyt.org>

COPYRIGHT
    Copyright 2001, 2002, 2007 by Audrey Tang <cpan@audreyt.org>.

    This software is released under the MIT license cited below.

  The "MIT" License
    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.