parent(3perl) Perl Programmers Reference Guide parent(3perl)

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

package Baz;
use parent qw(Foo Bar);

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';

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

base
parent::versioned
A fork of parent that provides version checking in parent class modules.

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

Max Maischein " corion@cpan.org "

Copyright (c) 2007-2017 Max Maischein "<corion@cpan.org>" Based on the idea of "base.pm", which was introduced with Perl 5.004_04.

This module is released under the same terms as Perl itself.
2021-05-23 perl v5.34.0