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CORION / parent-0.244 / lib / parent.pm 

            

              
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package parent;
use strict;
our $VERSION = '0.244';
sub import {
    my $class = shift;
    my $inheritor = caller(0);
    if ( @_ and $_[0] eq '-norequire' ) {
        shift @_;
    } else {
        for ( my @filename = @_ ) {
            local @_; # protect us against the loaded module changing @_
            s{::|'}{/}g;
            require "$_.pm"; # dies if the file is not found
        }
    }
    {
        no strict 'refs';
        push @{"$inheritor\::ISA"}, @_; # dies if a loop is detected
    };
};
1;
__END__
=encoding utf8
=head1 NAME
parent - Establish an ISA relationship with base classes at compile time
=head1 SYNOPSIS
    package Baz;
    use parent qw(Foo Bar);
=head1 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 C<parent> not to load any modules by using the C<-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 C<require> would
not consider an eligible filename (that is, it does not end in
either C<.pm> or C<.pmc>), use the following code:
  package MySecondPlugin;
  require './plugins/custom.plugin'; # contains Plugin::Custom
  use parent -norequire, 'Plugin::Custom';
=head1 HISTORY
This module was forked from L<base> to remove the cruft
that had accumulated in it.
=head1 CAVEATS
=head1 SEE ALSO
=over 4
=item L<base>
=item L<parent::versioned>
A fork of L<parent> that provides version checking in parent class modules.
=back
=head1 AUTHORS AND CONTRIBUTORS
Rafaël Garcia-Suarez, Bart Lateur, Max Maischein, Anno Siegel, Michael Schwern
=head1 MAINTAINER
Max Maischein C< corion@cpan.org >
Copyright (c) 2007-2017 Max Maischein C<< <corion@cpan.org> >>
Based on the idea of C<base.pm>, which was introduced with Perl 5.004_04.
=head1 LICENSE
This module is released under the same terms as Perl itself.
=cut