parent.3pm

Langue: en

Version: 2010-04-26 (MeeGo - 06/11/10)

Section: 3 (Bibliothèques de fonctions)

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.
     use 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

Rafae.l Garcia-Suarez, Bart Lateur, Max Maischein, Anno Siegel, Michael Schwern

MAINTAINER

Max Maischein " corion@cpan.org "

Copyright (c) 2007 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.