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- "use strict";
- function arrayMove(src, srcIndex, dst, dstIndex, len) {
- for (var j = 0; j < len; ++j) {
- dst[j + dstIndex] = src[j + srcIndex];
- src[j + srcIndex] = void 0;
- }
- }
-
- function Queue(capacity) {
- this._capacity = capacity;
- this._length = 0;
- this._front = 0;
- }
-
- Queue.prototype._willBeOverCapacity = function (size) {
- return this._capacity < size;
- };
-
- Queue.prototype._pushOne = function (arg) {
- var length = this.length();
- this._checkCapacity(length + 1);
- var i = (this._front + length) & (this._capacity - 1);
- this[i] = arg;
- this._length = length + 1;
- };
-
- Queue.prototype.push = function (fn, receiver, arg) {
- var length = this.length() + 3;
- if (this._willBeOverCapacity(length)) {
- this._pushOne(fn);
- this._pushOne(receiver);
- this._pushOne(arg);
- return;
- }
- var j = this._front + length - 3;
- this._checkCapacity(length);
- var wrapMask = this._capacity - 1;
- this[(j + 0) & wrapMask] = fn;
- this[(j + 1) & wrapMask] = receiver;
- this[(j + 2) & wrapMask] = arg;
- this._length = length;
- };
-
- Queue.prototype.shift = function () {
- var front = this._front,
- ret = this[front];
-
- this[front] = undefined;
- this._front = (front + 1) & (this._capacity - 1);
- this._length--;
- return ret;
- };
-
- Queue.prototype.length = function () {
- return this._length;
- };
-
- Queue.prototype._checkCapacity = function (size) {
- if (this._capacity < size) {
- this._resizeTo(this._capacity << 1);
- }
- };
-
- Queue.prototype._resizeTo = function (capacity) {
- var oldCapacity = this._capacity;
- this._capacity = capacity;
- var front = this._front;
- var length = this._length;
- var moveItemsCount = (front + length) & (oldCapacity - 1);
- arrayMove(this, 0, this, oldCapacity, moveItemsCount);
- };
-
- module.exports = Queue;
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