Current File : //usr/local/apps/perl/man/man3/Clone.3
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.\" ========================================================================
.\"
.IX Title "Clone 3"
.TH Clone 3 "2024-08-17" "perl v5.30.0" "User Contributed Perl Documentation"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
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.SH "NAME"
Clone \- recursively copy Perl datatypes
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\&    use Clone \*(Aqclone\*(Aq;
\&
\&    my $data = {
\&       set => [ 1 .. 50 ],
\&       foo => {
\&           answer => 42,
\&           object => SomeObject\->new,
\&       },
\&    };
\&
\&    my $cloned_data = clone($data);
\&
\&    $cloned_data\->{foo}{answer} = 1;
\&    print $cloned_data\->{foo}{answer};  # \*(Aq1\*(Aq
\&    print $data\->{foo}{answer};         # \*(Aq42\*(Aq
.Ve
.PP
You can also add it to your class:
.PP
.Vb 3
\&    package Foo;
\&    use parent \*(AqClone\*(Aq;
\&    sub new { bless {}, shift }
\&
\&    package main;
\&
\&    my $obj = Foo\->new;
\&    my $copy = $obj\->clone;
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
This module provides a \f(CW\*(C`clone()\*(C'\fR method which makes recursive
copies of nested hash, array, scalar and reference types,
including tied variables and objects.
.PP
\&\f(CW\*(C`clone()\*(C'\fR takes a scalar argument and duplicates it. To duplicate lists,
arrays or hashes, pass them in by reference, e.g.
.PP
.Vb 1
\&    my $copy = clone (\e@array);
\&
\&    # or
\&
\&    my %copy = %{ clone (\e%hash) };
.Ve
.SH "SEE ALSO"
.IX Header "SEE ALSO"
Storable's \f(CW\*(C`dclone()\*(C'\fR is a flexible solution for cloning variables,
albeit slower for average-sized data structures. Simple
and naive benchmarks show that Clone is faster for data structures
with 3 or fewer levels, while \f(CW\*(C`dclone()\*(C'\fR can be faster for structures
4 or more levels deep.
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 2001\-2022 Ray Finch. All Rights Reserved.
.PP
This module is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
.SH "AUTHOR"
.IX Header "AUTHOR"
Ray Finch \f(CW\*(C`<rdf@cpan.org>\*(C'\fR
.PP
Breno G. de Oliveira \f(CW\*(C`<garu@cpan.org>\*(C'\fR,
Nicolas Rochelemagne \f(CW\*(C`<atoomic@cpan.org>\*(C'\fR
and
Florian Ragwitz \f(CW\*(C`<rafl@debian.org>\*(C'\fR perform routine maintenance
releases since 2012.