|
package parent;
|
|
use strict;
|
|
use vars qw($VERSION);
|
|
$VERSION = '0.221';
|
|
|
|
sub import {
|
|
my $class = shift;
|
|
|
|
my $inheritor = caller(0);
|
|
|
|
if ( @_ and $_[0] eq '-norequire' ) {
|
|
shift @_;
|
|
} else {
|
|
for ( my @filename = @_ ) {
|
|
if ( $_ eq $inheritor ) {
|
|
warn "Class '$inheritor' tried to inherit from itself\n";
|
|
};
|
|
|
|
s{::|'}{/}g;
|
|
require "$_.pm"; # dies if the file is not found
|
|
}
|
|
}
|
|
|
|
{
|
|
no strict 'refs';
|
|
# This is more efficient than push for the new MRO
|
|
# at least until the new MRO is fixed
|
|
@{"$inheritor\::ISA"} = (@{"$inheritor\::ISA"} , @_);
|
|
};
|
|
};
|
|
|
|
"All your base are belong to us"
|
|
|
|
__END__
|
|
|
|
=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';
|
|
|
|
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 DIAGNOSTICS
|
|
|
|
=over 4
|
|
|
|
=item Class 'Foo' tried to inherit from itself
|
|
|
|
Attempting to inherit from yourself generates a warning.
|
|
|
|
use Foo;
|
|
use parent 'Foo';
|
|
|
|
=back
|
|
|
|
=head1 HISTORY
|
|
|
|
This module was forked from L<base> to remove the cruft
|
|
that had accumulated in it.
|
|
|
|
=head1 CAVEATS
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<base>
|
|
|
|
=head1 AUTHORS AND CONTRIBUTORS
|
|
|
|
Rafa?l Garcia-Suarez, Bart Lateur, Max Maischein, Anno Siegel, Michael Schwern
|
|
|
|
=head1 MAINTAINER
|
|
|
|
Max Maischein C< corion@cpan.org >
|
|
|
|
Copyright (c) 2007 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
|