4 , callable = require('es5-ext/object/valid-callable')
6 , apply = Function.prototype.apply, call = Function.prototype.call
7 , create = Object.create, defineProperty = Object.defineProperty
8 , defineProperties = Object.defineProperties
9 , hasOwnProperty = Object.prototype.hasOwnProperty
10 , descriptor = { configurable: true, enumerable: false, writable: true }
12 , on, once, off, emit, methods, descriptors, base;
14 on = function (type, listener) {
19 if (!hasOwnProperty.call(this, '__ee__')) {
20 data = descriptor.value = create(null);
21 defineProperty(this, '__ee__', descriptor);
22 descriptor.value = null;
26 if (!data[type]) data[type] = listener;
27 else if (typeof data[type] === 'object') data[type].push(listener);
28 else data[type] = [data[type], listener];
33 once = function (type, listener) {
38 on.call(this, type, once = function () {
39 off.call(self, type, once);
40 apply.call(listener, this, arguments);
43 once.__eeOnceListener__ = listener;
47 off = function (type, listener) {
48 var data, listeners, candidate, i;
52 if (!hasOwnProperty.call(this, '__ee__')) return this;
54 if (!data[type]) return this;
55 listeners = data[type];
57 if (typeof listeners === 'object') {
58 for (i = 0; (candidate = listeners[i]); ++i) {
59 if ((candidate === listener) ||
60 (candidate.__eeOnceListener__ === listener)) {
61 if (listeners.length === 2) data[type] = listeners[i ? 0 : 1];
62 else listeners.splice(i, 1);
66 if ((listeners === listener) ||
67 (listeners.__eeOnceListener__ === listener)) {
75 emit = function (type) {
76 var i, l, listener, listeners, args;
78 if (!hasOwnProperty.call(this, '__ee__')) return;
79 listeners = this.__ee__[type];
80 if (!listeners) return;
82 if (typeof listeners === 'object') {
84 args = new Array(l - 1);
85 for (i = 1; i < l; ++i) args[i - 1] = arguments[i];
87 listeners = listeners.slice();
88 for (i = 0; (listener = listeners[i]); ++i) {
89 apply.call(listener, this, args);
92 switch (arguments.length) {
94 call.call(listeners, this);
97 call.call(listeners, this, arguments[1]);
100 call.call(listeners, this, arguments[1], arguments[2]);
103 l = arguments.length;
104 args = new Array(l - 1);
105 for (i = 1; i < l; ++i) {
106 args[i - 1] = arguments[i];
108 apply.call(listeners, this, args);
127 base = defineProperties({}, descriptors);
129 module.exports = exports = function (o) {
130 return (o == null) ? create(base) : defineProperties(Object(o), descriptors);
132 exports.methods = methods;