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NAME
    Clone::PP - Recursively copy Perl datatypes

SYNOPSIS
      use Clone::PP qw(clone);
  
      $item = { 'foo' => 'bar', 'move' => [ 'zig', 'zag' ]  };
      $copy = clone( $item );

      $item = [ 'alpha', 'beta', { 'gamma' => 'vlissides' } ];
      $copy = clone( $item );

      $item = Foo->new();
      $copy = clone( $item );

    Or as an object method:

      require Clone::PP;
      push @Foo::ISA, 'Clone::PP';
  
      $item = Foo->new();
      $copy = $item->clone();

DESCRIPTION
    This module provides a general-purpose clone function to make deep
    copies of Perl data structures. It calls itself recursively to copy
    nested hash, array, scalar and reference types, including tied variables
    and objects.

    The clone() function takes a scalar argument to copy. To duplicate
    arrays or hashes, pass them in by reference:

      my $copy = clone(\@array);    my @copy = @{ clone(\@array) };
      my $copy = clone(\%hash);     my %copy = %{ clone(\%hash) };

    The clone() function also accepts an optional second parameter that can
    be used to limit the depth of the copy. If you pass a limit of 0, clone
    will return the same value you supplied; for a limit of 1, a shallow
    copy is constructed; for a limit of 2, two layers of copying are done,
    and so on.

      my $shallow_copy = clone( $item, 1 );

    To allow objects to intervene in the way they are copied, the clone()
    function checks for a couple of optional methods. If an object provides
    a method named "clone_self", it is called and the result returned
    without further processing. Alternately, if an object provides a method
    named "clone_init", it is called on the copied object before it is
    returned.

BUGS
    Some data types, such as globs, regexes, and code refs, are always
    copied shallowly.

    References to hash elements are not properly duplicated. (This is why
    two tests in t/dclone.t that are marked "todo".) For example, the
    following test should succeed but does not:

      my $hash = { foo => 1 }; 
      $hash->{bar} = \{ $hash->{foo} }; 
      my $copy = clone( \%hash ); 
      $hash->{foo} = 2; 
      $copy->{foo} = 2; 
      ok( $hash->{bar} == $copy->{bar} );

    To report bugs via the CPAN web tracking system, go to
    "http://rt.cpan.org/NoAuth/Bugs.html?Dist=Clone-PP" or send mail to
    "Dist=Clone-PP#rt.cpan.org", replacing "#" with "@".

SEE ALSO
    For a faster implementation in XS, see the clone entry in the Clone
    manpage, the clone entry in the Util manpage, or <Storable/dclone>.

CREDITS AND COPYRIGHT
    Developed by Matthew Simon Cavalletto at Evolution Softworks. More free
    Perl software is available at "www.evoscript.org".

    Copyright 2003 Matthew Simon Cavalletto. You may contact the author
    directly at "[email protected]" or "[email protected]".

    Code initially derived from Ref.pm. Portions Copyright 1994 David Muir
    Sharnoff.

    Interface based by Clone by Ray Finch with contributions from
    chocolateboy. Portions Copyright 2001 Ray Finch. Portions Copyright 2001
    chocolateboy.

    You may use, modify, and distribute this software under the same terms
    as Perl.