36 lines
767 B
JavaScript
Executable file
36 lines
767 B
JavaScript
Executable file
'use strict';
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var toStr = Object.prototype.toString;
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var hasSymbols = require('has-symbols')();
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if (hasSymbols) {
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var symToStr = Symbol.prototype.toString;
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var symStringRegex = /^Symbol\(.*\)$/;
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var isSymbolObject = function isRealSymbolObject(value) {
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if (typeof value.valueOf() !== 'symbol') {
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return false;
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}
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return symStringRegex.test(symToStr.call(value));
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};
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module.exports = function isSymbol(value) {
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if (typeof value === 'symbol') {
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return true;
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}
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if (toStr.call(value) !== '[object Symbol]') {
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return false;
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}
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try {
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return isSymbolObject(value);
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} catch (e) {
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return false;
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}
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};
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} else {
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module.exports = function isSymbol(value) {
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// this environment does not support Symbols.
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return false && value;
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};
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}
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