source: gs3-extensions/web-audio/trunk/js-mad/sink.js-master/src/event-emitter.js@ 28388

void function (Sink) {

/**
 * A light event emitter.
 *
 * @class
 * @static Sink
*/
function EventEmitter () {
    var k;
    for (k in EventEmitter.prototype) {
        if (EventEmitter.prototype.hasOwnProperty(k)) {
            this[k] = EventEmitter.prototype[k];
        }
    }
    this._listeners = {};
}

EventEmitter.prototype = {
    _listeners: null,
/**
 * Emits an event.
 *
 * @method EventEmitter
 *
 * @arg {String} name The name of the event to emit.
 * @arg {Array} args The arguments to pass to the event handlers.
*/
    emit: function (name, args) {
        if (this._listeners[name]) {
            for (var i=0; i<this._listeners[name].length; i++) {
                this._listeners[name][i].apply(this, args);
            }
        }
        return this;
    },
/**
 * Adds an event listener to an event.
 *
 * @method EventEmitter
 *
 * @arg {String} name The name of the event.
 * @arg {Function} listener The event listener to attach to the event.
*/
    on: function (name, listener) {
        this._listeners[name] = this._listeners[name] || [];
        this._listeners[name].push(listener);
        return this;
    },
/**
 * Adds an event listener to an event.
 *
 * @method EventEmitter
 *
 * @arg {String} name The name of the event.
 * @arg {Function} !listener The event listener to remove from the event. If not specified, will delete all.
*/
    off: function (name, listener) {
        if (this._listeners[name]) {
            if (!listener) {
                delete this._listeners[name];
                return this;
            }

            for (var i=0; i<this._listeners[name].length; i++) {
                if (this._listeners[name][i] === listener) {
                    this._listeners[name].splice(i--, 1);
                }
            }

            if (!this._listeners[name].length) {
                delete this._listeners[name];
            }
        }
        return this;
    }
};

Sink.EventEmitter = EventEmitter;

EventEmitter.call(Sink);

}(this.Sink);