1
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'use strict';
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2
|
|
3
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var toStr = Object.prototype.toString;
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4
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var hasSymbols = require('has-symbols')();
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5
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|
6
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if (hasSymbols) {
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7
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var symToStr = Symbol.prototype.toString;
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8
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var symStringRegex = /^Symbol\(.*\)$/;
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9
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var isSymbolObject = function isRealSymbolObject(value) {
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10
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if (typeof value.valueOf() !== 'symbol') {
|
11
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return false;
|
12
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}
|
13
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return symStringRegex.test(symToStr.call(value));
|
14
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};
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15
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|
16
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module.exports = function isSymbol(value) {
|
17
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if (typeof value === 'symbol') {
|
18
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return true;
|
19
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}
|
20
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if (toStr.call(value) !== '[object Symbol]') {
|
21
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return false;
|
22
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}
|
23
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try {
|
24
|
return isSymbolObject(value);
|
25
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} catch (e) {
|
26
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return false;
|
27
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}
|
28
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};
|
29
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} else {
|
30
|
|
31
|
module.exports = function isSymbol(value) {
|
32
|
// this environment does not support Symbols.
|
33
|
return false && value;
|
34
|
};
|
35
|
}
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