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31 lines
795 B
JavaScript
31 lines
795 B
JavaScript
/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this file,
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* You can obtain one at http://mozilla.org/MPL/2.0/. */
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this.EXPORTED_SYMBOLS = ["Queue"];
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this.Queue = function Queue() {
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this._queue = [];
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this._index = 0;
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}
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Queue.prototype = {
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getLength: function() { return (this._queue.length - this._index); },
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isEmpty: function() { return (this._queue.length == 0); },
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enqueue: function(item) { this._queue.push(item); },
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dequeue: function() {
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if(this.isEmpty())
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return undefined;
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var item = this._queue[this._index];
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if (++this._index * 2 >= this._queue.length){
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this._queue = this._queue.slice(this._index);
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this._index = 0;
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}
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return item;
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}
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}
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