A minimalistic CoffeeScript event emitter.

EventEmitter.coffee

# A minimalistic CoffeeScript event emitter.
# Jannis R <[email protected]>
# https://gist.github.com/derhuerst/5433f5ee3342a1de6d81



class EventEmitter

	constructor: ->
		@_events = {}

	emit: (event, args...) ->
		handler args... for handler in @_events[event]
		return this

	on: (event, handler) ->
		@_events[event] ?= []
		@_events[event].push handler
		return this

	off: (event, handler) ->
		@_events[event].splice @_events[event].indexOf(handler), 1
		return this

	once: (event, handler) ->
		fn = =>
			@off event, fn
			handler arguments...
		@on event, fn
		return this