43 lines
1.2 KiB
JavaScript
43 lines
1.2 KiB
JavaScript
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var wmUniqueIndex = Math.round(Math.random() * 9);
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var supportDefineProperty = typeof Object.defineProperty === 'function';
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var WeakMap = (function () {
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function WeakMap() {
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this._id = '__ec_inner_' + wmUniqueIndex++;
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}
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WeakMap.prototype.get = function (key) {
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return this._guard(key)[this._id];
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};
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WeakMap.prototype.set = function (key, value) {
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var target = this._guard(key);
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if (supportDefineProperty) {
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Object.defineProperty(target, this._id, {
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value: value,
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enumerable: false,
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configurable: true
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});
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}
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else {
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target[this._id] = value;
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}
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return this;
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};
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WeakMap.prototype["delete"] = function (key) {
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if (this.has(key)) {
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delete this._guard(key)[this._id];
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return true;
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}
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return false;
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};
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WeakMap.prototype.has = function (key) {
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return !!this._guard(key)[this._id];
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};
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WeakMap.prototype._guard = function (key) {
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if (key !== Object(key)) {
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throw TypeError('Value of WeakMap is not a non-null object.');
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}
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return key;
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};
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return WeakMap;
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}());
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export default WeakMap;
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