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21 lines
548 B
21 lines
548 B
4 years ago
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"use strict";
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var global = require("ext/global-this")
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, validTypes = { object: true, symbol: true };
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module.exports = function () {
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var Symbol = global.Symbol;
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var symbol;
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if (typeof Symbol !== "function") return false;
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symbol = Symbol("test symbol");
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try { String(symbol); }
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catch (e) { return false; }
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// Return 'true' also for polyfills
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if (!validTypes[typeof Symbol.iterator]) return false;
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if (!validTypes[typeof Symbol.toPrimitive]) return false;
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if (!validTypes[typeof Symbol.toStringTag]) return false;
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return true;
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};
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