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# parent

Perl 5 version 26.0 documentation
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# parent

- NAME
- SYNOPSIS
- DESCRIPTION
- HISTORY
- CAVEATS
- SEE ALSO
- AUTHORS AND CONTRIBUTORS
- MAINTAINER
- LICENSE

# NAME

parent - Establish an ISA relationship with base classes at compile time

# SYNOPSIS

        package Baz;    use parent qw(Foo Bar);

# DESCRIPTION

Allows you to both load one or more modules, while setting up inheritance from those modules at the same time. Mostly similar in effect to

        package Baz;    BEGIN {        require Foo;        require Bar;        push @ISA, qw(Foo Bar);    }

By default, every base class needs to live in a file of its own. If you want to have a subclass and its parent class in the same file, you can tell `parent` not to load any modules by using the `-norequire` switch:

      package Foo;  sub exclaim { "I CAN HAS PERL" }  package DoesNotLoadFooBar;  use parent -norequire, 'Foo', 'Bar';  # will not go looking for Foo.pm or Bar.pm

This is equivalent to the following code:

      package Foo;  sub exclaim { "I CAN HAS PERL" }  package DoesNotLoadFooBar;  push @DoesNotLoadFooBar::ISA, 'Foo', 'Bar';

This is also helpful for the case where a package lives within a differently named file:

      package MyHash;  use Tie::Hash;  use parent -norequire, 'Tie::StdHash';

This is equivalent to the following code:

      package MyHash;  require Tie::Hash;  push @ISA, 'Tie::StdHash';

If you want to load a subclass from a file that `require` would not consider an eligible filename (that is, it does not end in either `.pm` or `.pmc`), use the following code:

      package MySecondPlugin;  require './plugins/custom.plugin'; # contains Plugin::Custom  use parent -norequire, 'Plugin::Custom';

# HISTORY

This module was forked from base to remove the cruft that had accumulated in it.

# CAVEATS

# SEE ALSO

base

# AUTHORS AND CONTRIBUTORS

Rafaël Garcia-Suarez, Bart Lateur, Max Maischein, Anno Siegel, Michael Schwern

# MAINTAINER

Max Maischein `corion@cpan.org`

Copyright (c) 2007-10 Max Maischein `<corion@cpan.org>` Based on the idea of `base.pm` , which was introduced with Perl 5.004_04.

# LICENSE

This module is released under the same terms as Perl itself.

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- NAME
- SYNOPSIS
- DESCRIPTION
- HISTORY
- CAVEATS
- SEE ALSO
- AUTHORS AND CONTRIBUTORS
- MAINTAINER
- LICENSE