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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;
    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 or

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';


Class 'Foo' tried to inherit from itself

Attempting to inherit from yourself generates a warning.

use Foo;
use parent 'Foo';


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





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


Max Maischein

Copyright (c) 2007 Max Maischein <> Based on the idea of, which was introduced with Perl 5.004_04.


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

1 POD Error

The following errors were encountered while parsing the POD:

Around line 123:

Non-ASCII character seen before =encoding in 'Rafaël'. Assuming CP1252