58 lines
1.2 KiB
JavaScript
58 lines
1.2 KiB
JavaScript
'use strict';
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var inherits = require('inherits')
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, EventTarget = require('./eventtarget')
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;
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function EventEmitter() {
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EventTarget.call(this);
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}
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inherits(EventEmitter, EventTarget);
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EventEmitter.prototype.removeAllListeners = function(type) {
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if (type) {
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delete this._listeners[type];
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} else {
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this._listeners = {};
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}
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};
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EventEmitter.prototype.once = function(type, listener) {
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var self = this
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, fired = false;
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function g() {
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self.removeListener(type, g);
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if (!fired) {
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fired = true;
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listener.apply(this, arguments);
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}
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}
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this.on(type, g);
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};
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EventEmitter.prototype.emit = function() {
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var type = arguments[0];
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var listeners = this._listeners[type];
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if (!listeners) {
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return;
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}
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// equivalent of Array.prototype.slice.call(arguments, 1);
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var l = arguments.length;
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var args = new Array(l - 1);
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for (var ai = 1; ai < l; ai++) {
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args[ai - 1] = arguments[ai];
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}
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for (var i = 0; i < listeners.length; i++) {
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listeners[i].apply(this, args);
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}
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};
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EventEmitter.prototype.on = EventEmitter.prototype.addListener = EventTarget.prototype.addEventListener;
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EventEmitter.prototype.removeListener = EventTarget.prototype.removeEventListener;
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module.exports.EventEmitter = EventEmitter;
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