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1 liveuser 1 
/**
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 * Expose the _EventTarget class.
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 */
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module.exports = _EventTarget;
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function _EventTarget() {
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	// Do nothing if called for a native EventTarget object..
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	if (typeof this.addEventListener === 'function') {
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		return;
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	}
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	this._listeners = {};
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	this.addEventListener = _addEventListener;
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	this.removeEventListener = _removeEventListener;
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	this.dispatchEvent = _dispatchEvent;
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}
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Object.defineProperties(_EventTarget.prototype, {
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	listeners: {
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		get: function () {
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			return this._listeners;
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		}
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	}
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});
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function _addEventListener(type, newListener) {
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	var listenersType,
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		i, listener;
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	if (!type || !newListener) {
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		return;
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	}
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	listenersType = this._listeners[type];
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	if (listenersType === undefined) {
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		this._listeners[type] = listenersType = [];
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	}
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	for (i = 0; !!(listener = listenersType[i]); i++) {
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		if (listener === newListener) {
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			return;
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		}
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	}
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	listenersType.push(newListener);
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}
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function _removeEventListener(type, oldListener) {
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	var listenersType,
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		i, listener;
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	if (!type || !oldListener) {
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		return;
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	}
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	listenersType = this._listeners[type];
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	if (listenersType === undefined) {
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		return;
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	}
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	for (i = 0; !!(listener = listenersType[i]); i++) {
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		if (listener === oldListener) {
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			listenersType.splice(i, 1);
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			break;
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		}
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	}
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	if (listenersType.length === 0) {
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		delete this._listeners[type];
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	}
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}
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function _dispatchEvent(event) {
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	var type,
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		listenersType,
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		dummyListener,
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		stopImmediatePropagation = false,
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		i, listener;
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	if (!event || typeof event.type !== 'string') {
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		throw new Error('`event` must have a valid `type` property');
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	}
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	if (event._dispatched) {
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		throw new Error('event already dispatched');
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	}
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	event._dispatched = true;
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	// Force the event to be cancelable.
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	event.cancelable = true;
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	event.target = this;
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	// Override stopImmediatePropagation() function.
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	event.stopImmediatePropagation = function () {
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		stopImmediatePropagation = true;
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	};
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	type = event.type;
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	listenersType = (this._listeners[type] || []);
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	dummyListener = this['on' + type];
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	if (typeof dummyListener === 'function') {
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		listenersType.push(dummyListener);
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	}
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	for (i = 0; !!(listener = listenersType[i]); i++) {
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		if (stopImmediatePropagation) {
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			break;
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		}
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		listener.call(this, event);
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	}
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	return !event.defaultPrevented;
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}