NAME

       Module::Pluggable::Ordered - Call module plugins in a specified order

SYNOPSIS

           package Foo;
           use Module::Pluggable::Ordered;

           Foo->call_plugins("some_event", @stuff);

               for my $plugin (Foo->plugins()){
                       $plugin->method();
               }

       Meanwhile, in a nearby module...

           package Foo::Plugin::One;
           sub some_event_order { 99 } # I get called last of all
           sub some_event { my ($self, @stuff) = @_; warn "Hello!" }

               sub _order { 99 } # I get listed by plugins_ordered() last

       And in another:

           package Foo::Plugin::Two;
           sub some_event_order { 13 } # I get called relatively early
           sub some_event { ... }

               sub _order { 10 } # I get listed by plugins_ordered() early

DESCRIPTION

       This module behaves exactly the same as "Module::Pluggable", supporting all of its options, but also
       mixes in the "call_plugins" and "plugins_ordered" methods to your class. "call_plugins" acts a little
       like "Class::Trigger"; it takes the name of a method, and some parameters. Let's say we call it like so:

           __PACKAGE__->call_plugins("my_method", @something);

       "call_plugins" looks at the plugin modules found using "Module::Pluggable" for ones which provide
       "my_method_order". It sorts the modules numerically based on the result of this method, and then calls
       "$_->my_method(@something)" on them in order. This produces an effect a little like the System V init
       process, where files can specify where in the init sequence they want to be called.

       "plugins_ordered" extends the "plugins" method created by "Module::Pluggable" to list the plugins in
       defined order. It looks for a "_order" method in the modules found using "Module::Pluggable", and returns
       the modules sorted numerically in that order. For example:

               my @plugins = __PACKAGE__->plugins();

       The resulting array of plugins will be sorted. If no "_order" subroutine is defined for a module, an
       arbitrary default value of 50 is used.

OPTIONS

       The "package" option can be used to put the pluggability into another package, to be used for modules
       building on the functionality of this one.

       It also provides the "only" and "except" options.

            # will only return the Foo::Plugin::Quux plugin
            use Module::Pluggable::Ordered only => [ "Foo::Plugin::Quux" ];

            # will not return the Foo::Plugin::Quux plugin
            use Module::Pluggable::Ordered except => [ "Foo::Plugin::Quux" ];

SEE ALSO

       Module::Pluggable, Class::Trigger

AUTHOR

       Simon Cozens, <simon@cpan.org> (author emeritus)

       Christopher Nehren, <apeiron@cpan.org> (current maintainer)

       Please report bugs via the CPAN RT tracker at http://rt.cpan.org.

COPYRIGHT AND LICENSE

       Copyright 2004 by Simon Cozens

       Copyright 2004 by Christopher Nehren (current copyright holder)

       This library is free software; you can redistribute it and/or modify it under the same terms as Perl
       itself.

ACKNOWLEDGEMENTS

       Thank you to Simon Cozens for originally writing this module.

       Thanks to Lars Thegler for indirectly alerting me to the fact that my POD was horribly broken, for
       providing patches to make this module work with Perl versions < 5.6, for maintaining the port up to
       version 1.3, and for allowing me to take maintainership for versions 1.3 onwards.