NAME

Venus::Role::Subscribable - Subscribable Role

ABSTRACT

Subscribable Role for Perl 5

SYNOPSIS

package Example;

use Venus::Class;

with 'Venus::Role::Subscribable';

sub execute {
  $_[0]->publish('on.execute');
}

package main;

my $example = Example->new;

# $example->subscribe('on.execute', sub{...});

# bless(..., 'Example')

# $example->publish('on.execute');

# bless(..., 'Example')

DESCRIPTION

This package provides a mechanism for publishing and subscribing to events.

METHODS

This package provides the following methods:

publish

publish(Str $name, Any @args) (Self)

The publish method notifies all subscribers for a given event and returns the invocant.

Since 1.75

publish example 1
# given: synopsis

package main;

$example = $example->publish;

# bless(..., 'Example')
publish example 2
# given: synopsis

package main;

$example = $example->publish('on.execute');

# bless(..., 'Example')
publish example 3
# given: synopsis

package main;

$example->subscribe('on.execute', sub {$example->{emitted} = [@_]});

$example = $example->publish('on.execute');

# bless(..., 'Example')
publish example 4
# given: synopsis

package main;

$example->subscribe('on.execute', sub {$example->{emitted} = [@_]});

$example = $example->publish('on.execute', [1..4]);

# bless(..., 'Example')

subscribe

subscribe(Str $name, CodeRef $code) (Self)

The subscribe method registers a subscribers (i.e. callbacks) for a given event, and returns the invocant.

Since 1.75

subscribe example 1
# given: synopsis

package main;

$example = $example->subscribe('on.execute', sub {$example->{emitted} = [@_]});

# bless(..., 'Example')
subscribe example 2
# given: synopsis

package main;

$example = $example->subscribe('on.execute', sub {$example->{emitted_1} = [@_]});

# bless(..., 'Example')

$example = $example->subscribe('on.execute', sub {$example->{emitted_2} = [@_]});

# bless(..., 'Example')

$example = $example->subscribe('on.execute', sub {$example->{emitted_3} = [@_]});

# bless(..., 'Example')

# $example->publish('on.execute');

# bless(..., 'Example')

subscribers

subscribers(Str $name) (Int)

The subscribers method returns the number of subscribers (i.e. callbacks) for a given event.

Since 1.75

subscribers example 1
# given: synopsis

package main;

$example = $example->subscribers;

# 0
subscribers example 2
# given: synopsis

package main;

$example = $example->subscribers('on.execute');

# 0
subscribers example 3
# given: synopsis

package main;

$example = $example->subscribe('on.execute', sub {$example->{emitted_1} = [@_]});

$example = $example->subscribe('on.execute', sub {$example->{emitted_2} = [@_]});

$example = $example->subscribe('on.execute', sub {$example->{emitted_3} = [@_]});

$example = $example->subscribers('on.execute');

# 3

unsubscribe

unsubscribe(Str $name, CodeRef $code) (Self)

The unsubscribe method deregisters all subscribers (i.e. callbacks) for a given event, or a specific callback if provided, and returns the invocant.

Since 1.75

unsubscribe example 1
# given: synopsis

package main;

$example = $example->unsubscribe;

# bless(..., 'Example')
unsubscribe example 2
# given: synopsis

package main;

$example = $example->unsubscribe('on.execute');

# bless(..., 'Example')
unsubscribe example 3
# given: synopsis

package main;

$example = $example->subscribe('on.execute', sub {$example->{emitted_1} = [@_]});

$example = $example->subscribe('on.execute', sub {$example->{emitted_2} = [@_]});

$example = $example->subscribe('on.execute', sub {$example->{emitted_3} = [@_]});

$example = $example->unsubscribe('on.execute');

# bless(..., 'Example')
unsubscribe example 4
# given: synopsis

package main;

my $execute = sub {$example->{execute} = [@_]};

$example = $example->subscribe('on.execute', $execute);

$example = $example->unsubscribe('on.execute', $execute);

# bless(..., 'Example')

AUTHORS

Awncorp, awncorp@cpan.org

LICENSE

Copyright (C) 2000, Al Newkirk.

This program is free software, you can redistribute it and/or modify it under the terms of the Apache license version 2.0.