events.js in stylus-source-0.54.5

- old
+ new

@@ -1,33 +1,44 @@
+'use strict';
+
 /**
  * Module exports.
  */
 
 exports.EventEmitter = EventEmitter;
 
 /**
- * Check if `obj` is an array.
+ * Object#toString reference.
  */
+var objToString = Object.prototype.toString;
 
-function isArray(obj) {
-  return '[object Array]' == {}.toString.call(obj);
+/**
+ * Check if a value is an array.
+ *
+ * @api private
+ * @param {*} val The value to test.
+ * @return {boolean} true if the value is an array, otherwise false.
+ */
+function isArray (val) {
+  return objToString.call(val) === '[object Array]';
 }
 
 /**
  * Event emitter constructor.
  *
  * @api public
  */
+function EventEmitter () {}
 
-function EventEmitter(){};
-
 /**
- * Adds a listener.
+ * Add a listener.
  *
  * @api public
+ * @param {string} name Event name.
+ * @param {Function} fn Event handler.
+ * @return {EventEmitter} Emitter instance.
  */
-
 EventEmitter.prototype.on = function (name, fn) {
   if (!this.$events) {
     this.$events = {};
   }
 
@@ -46,32 +57,36 @@
 
 /**
  * Adds a volatile listener.
  *
  * @api public
+ * @param {string} name Event name.
+ * @param {Function} fn Event handler.
+ * @return {EventEmitter} Emitter instance.
  */
-
 EventEmitter.prototype.once = function (name, fn) {
   var self = this;
 
   function on () {
     self.removeListener(name, on);
     fn.apply(this, arguments);
-  };
+  }
 
   on.listener = fn;
   this.on(name, on);
 
   return this;
 };
 
 /**
- * Removes a listener.
+ * Remove a listener.
  *
  * @api public
+ * @param {string} name Event name.
+ * @param {Function} fn Event handler.
+ * @return {EventEmitter} Emitter instance.
  */
-
 EventEmitter.prototype.removeListener = function (name, fn) {
   if (this.$events && this.$events[name]) {
     var list = this.$events[name];
 
     if (isArray(list)) {
@@ -100,15 +115,16 @@
 
   return this;
 };
 
 /**
- * Removes all listeners for an event.
+ * Remove all listeners for an event.
  *
  * @api public
+ * @param {string} name Event name.
+ * @return {EventEmitter} Emitter instance.
  */
-
 EventEmitter.prototype.removeAllListeners = function (name) {
   if (name === undefined) {
     this.$events = {};
     return this;
   }
@@ -119,15 +135,16 @@
 
   return this;
 };
 
 /**
- * Gets all listeners for a certain event.
+ * Get all listeners for a given event.
  *
  * @api public
+ * @param {string} name Event name.
+ * @return {EventEmitter} Emitter instance.
  */
-
 EventEmitter.prototype.listeners = function (name) {
   if (!this.$events) {
     this.$events = {};
   }
 
@@ -141,15 +158,16 @@
 
   return this.$events[name];
 };
 
 /**
- * Emits an event.
+ * Emit an event.
  *
  * @api public
+ * @param {string} name Event name.
+ * @return {boolean} true if at least one handler was invoked, else false.
  */
-
 EventEmitter.prototype.emit = function (name) {
   if (!this.$events) {
     return false;
   }
 
@@ -157,12 +175,12 @@
 
   if (!handler) {
     return false;
   }
 
-  var args = [].slice.call(arguments, 1);
+  var args = Array.prototype.slice.call(arguments, 1);
 
-  if ('function' == typeof handler) {
+  if (typeof handler === 'function') {
     handler.apply(this, args);
   } else if (isArray(handler)) {
     var listeners = handler.slice();
 
     for (var i = 0, l = listeners.length; i < l; i++) {