18 lines
568 B
JavaScript
18 lines
568 B
JavaScript
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'use strict';
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var getBuiltIn = require('../internals/get-built-in');
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var uncurryThis = require('../internals/function-uncurry-this');
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var Symbol = getBuiltIn('Symbol');
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var keyFor = Symbol.keyFor;
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var thisSymbolValue = uncurryThis(Symbol.prototype.valueOf);
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// `Symbol.isRegisteredSymbol` method
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// https://tc39.es/proposal-symbol-predicates/#sec-symbol-isregisteredsymbol
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module.exports = Symbol.isRegisteredSymbol || function isRegisteredSymbol(value) {
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try {
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return keyFor(thisSymbolValue(value)) !== undefined;
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} catch (error) {
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return false;
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}
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};
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