# NAME

OO::Plugin – framework for working with OO plugins.

# SYNOPSIS

    use OO::Plugin;
    use OO::Plugin::Manager;

    class Foo is pluggable {
        has $.attr;
        method bar is pluggable {
            return 42;
        }
    }

    plugin Fubar {
        method a-bar ( $msg ) is plug-around( Foo => 'bar' ) {
            $msg.set-rc( pi ); # Will override &Foo::bar return value and prevent its execution.
        }
    }

    my $manager = OO::Plugin::Manager.new.initialize;
    my $instance = $manager.create( Foo, attr => 'some value' );
    say $instance.bar;  # 3.141592653589793

# DESCRIPTION

With this framework any application can have highly flexible and extensible plugin subsystem with which plugins would be capable of:

- method overriding

- class overriding (inheriting)

- callbacks

- asynchronous event handling

The framework also supports:

- automatic loading of plugins with a predefined namespace

- managing plugin ordering and dependencies

Not yet supported but planned for the future is plugin compatibility management.

Read more in OO::Plugin::Manual.

# EXPORTS

## Routines

- `plugin-meta [key =` value, ...]>

  Registers plugin meta. Can only be used within plugin body block.

- `plug-last [return-value]`

  Cancels current execution chain and optionally sets return value.

- `plug-redo`

  Restarts current execution chain.

## Classes

`PluginMessage` and <MethodHandlerMsg> are re-exported from OO::Plugin::Class.

# SEE ALSO

OO::Plugin::Manual, OO::Plugin::Manager, OO::Plugin::Class OO::Plugin::Registry

# AUTHOR

Vadim Belman <vrurg@cpan.org>