parent(3) User Contributed Perl Documentation parent(3)
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';
DIAGNOSTICS
Class 'Foo' tried to inherit from itself
Attempting to inherit from yourself generates a warning.
package Foo;
use parent 'Foo';
HISTORY
This module was forked from base to remove the cruft that had
accumulated in it.
CAVEATS
SEE ALSO
base
AUTHORS AND CONTRIBUTORS
Rafaeel Garcia-Suarez, Bart Lateur, Max Maischein, Anno Siegel, Michael
Schwern
MAINTAINER
Max Maischein " corion AT cpan.org "
Copyright (c) 2007-10 Max Maischein "<corion AT 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.
perl v5.16.3 2011-03-08 parent(3)