NAME
Mojo::EventEmitter - Event emitter base class
SYNOPSIS
package Cat;
use Mojo::Base 'Mojo::EventEmitter';
# Emit events
sub poke {
my $self = shift;
$self->emit(roar => 3);
}
package main;
# Subscribe to events
my $tiger = Cat->new;
$tiger->on(roar => sub {
my ($tiger, $times) = @_;
say 'RAWR!' for 1 .. $times;
});
$tiger->poke;DESCRIPTION
Mojo::EventEmitter is a simple base class for event emitting objects.
EVENTS
Mojo::EventEmitter can emit the following events.
error
$e->on(error => sub {
my ($e, $err) = @_;
...
});Emitted for event errors, fatal if unhandled.
$e->on(error => sub {
my ($e, $err) = @_;
say "This looks bad: $err";
});METHODS
Mojo::EventEmitter inherits all methods from Mojo::Base and implements the following new ones.
catch
$e = $e->catch(sub {...});Subscribe to "error" event.
# Longer version
$e->on(error => sub {...});emit
$e = $e->emit('foo');
$e = $e->emit('foo', 123);Emit event.
emit_safe
$e = $e->emit_safe('foo');
$e = $e->emit_safe('foo', 123);Emit event safely and emit "error" event on failure.
has_subscribers
my $bool = $e->has_subscribers('foo');Check if event has subscribers.
on
my $cb = $e->on(foo => sub {...});Subscribe to event.
$e->on(foo => sub {
my ($e, @args) = @_;
...
});once
my $cb = $e->once(foo => sub {...});Subscribe to event and unsubscribe again after it has been emitted once.
$e->once(foo => sub {
my ($e, @args) = @_;
...
});subscribers
my $subscribers = $e->subscribers('foo');All subscribers for event.
# Unsubscribe last subscriber
$e->unsubscribe(foo => $e->subscribers('foo')->[-1]);unsubscribe
$e = $e->unsubscribe('foo');
$e = $e->unsubscribe(foo => $cb);Unsubscribe from event.
DEBUGGING
You can set the MOJO_EVENTEMITTER_DEBUG environment variable to get some advanced diagnostics information printed to STDERR.
MOJO_EVENTEMITTER_DEBUG=1