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Data::Swap 0.08

To install this module type the following:

   perl Makefile.PL
   make
   make test
   make install


Module documentation:

NAME
    Data::Swap - Swap type and contents of variables

SYNOPSIS
        use Data::Swap;

        my $p = [];
        my $q = {};
        print "$p $q\n";            # ARRAY(0x965cc) HASH(0x966b0)
        swap $p, $q;                # swap referenced variables
        print "$p $q\n";            # HASH(0x965cc) ARRAY(0x966b0)

        my $x = {};
        my $y = $x;                 # $x and $y reference same var
        swap $x, [1, 2, 3];         # swap referenced var with an array
        print "@$y\n";              # 1 2 3

        use Data::Swap 'deref';

        my @refs = (\$x, \@y);
        $_++ for deref @refs;       # dereference a list of references

        # Note that I omitted \%z from the @refs because $_++ would fail 
        # on a key, but deref does work on hash-refs too of course.

DESCRIPTION
    This module allows you to swap the contents of two referenced variables,
    even if they have different types.

    The main application is to change the base type of an object after it
    has been created, for example for dynamic loading of data structures:

        swap $self, bless $replacement, $newclass;

    This module additionally contain the function "deref" which acts like a
    generic list-dereferencing operator.

FUNCTIONS
  swap REF1, REF2
    Swaps the contents (and if necessary, type) of two referenced variables.

  deref LIST
    Dereferences a list of scalar refs, array refs and hash refs. Mainly
    exists because you can't use "map" for this application, as it makes
    copies of the dereferenced values.

KNOWN ISSUES
    You can't "swap" an overloaded object with a non-overloaded one, unless
    you use Perl 5.10 or later.

    Also, don't use "swap" to change the type of a directly accessible
    variable -- like "swap \$x, \@y". That's just asking for segfaults.
    Unfortunately there is no good way for me to detect and prevent this.

AUTHOR
    Matthijs van Duin <xmath@cpan.org>

    Copyright (C) 2003, 2004, 2007, 2008 Matthijs van Duin. This program is
    free software; you can redistribute it and/or modify it under the same
    terms as Perl itself.

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