24 lines
556 B
JavaScript
24 lines
556 B
JavaScript
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"use strict";
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var d = require("d")
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, validateSymbol = require("../../../validate-symbol");
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var registry = Object.create(null);
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module.exports = function (SymbolPolyfill) {
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return Object.defineProperties(SymbolPolyfill, {
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for: d(function (key) {
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if (registry[key]) return registry[key];
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return (registry[key] = SymbolPolyfill(String(key)));
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}),
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keyFor: d(function (symbol) {
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var key;
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validateSymbol(symbol);
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for (key in registry) {
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if (registry[key] === symbol) return key;
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}
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return undefined;
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})
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});
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};
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