18 lines
474 B
JavaScript
18 lines
474 B
JavaScript
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'use strict';
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var validTypes = { object: true, symbol: true };
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module.exports = function () {
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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); } 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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