// `Symbol.prototype.description` getter
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// https://tc39.es/ecma262/#sec-symbol.prototype.description
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'use strict';
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var $ = require('../internals/export');
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var DESCRIPTORS = require('../internals/descriptors');
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var global = require('../internals/global');
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var uncurryThis = require('../internals/function-uncurry-this');
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var hasOwn = require('../internals/has-own-property');
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var isCallable = require('../internals/is-callable');
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var isPrototypeOf = require('../internals/object-is-prototype-of');
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var toString = require('../internals/to-string');
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var defineProperty = require('../internals/object-define-property').f;
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var copyConstructorProperties = require('../internals/copy-constructor-properties');
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var NativeSymbol = global.Symbol;
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var SymbolPrototype = NativeSymbol && NativeSymbol.prototype;
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if (DESCRIPTORS && isCallable(NativeSymbol) && (!('description' in SymbolPrototype) ||
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// Safari 12 bug
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NativeSymbol().description !== undefined
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)) {
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var EmptyStringDescriptionStore = {};
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// wrap Symbol constructor for correct work with undefined description
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var SymbolWrapper = function Symbol() {
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var description = arguments.length < 1 || arguments[0] === undefined ? undefined : toString(arguments[0]);
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var result = isPrototypeOf(SymbolPrototype, this)
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? new NativeSymbol(description)
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// in Edge 13, String(Symbol(undefined)) === 'Symbol(undefined)'
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: description === undefined ? NativeSymbol() : NativeSymbol(description);
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if (description === '') EmptyStringDescriptionStore[result] = true;
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return result;
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};
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copyConstructorProperties(SymbolWrapper, NativeSymbol);
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SymbolWrapper.prototype = SymbolPrototype;
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SymbolPrototype.constructor = SymbolWrapper;
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var NATIVE_SYMBOL = String(NativeSymbol('test')) == 'Symbol(test)';
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var symbolToString = uncurryThis(SymbolPrototype.toString);
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var symbolValueOf = uncurryThis(SymbolPrototype.valueOf);
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var regexp = /^Symbol\((.*)\)[^)]+$/;
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var replace = uncurryThis(''.replace);
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var stringSlice = uncurryThis(''.slice);
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defineProperty(SymbolPrototype, 'description', {
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configurable: true,
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get: function description() {
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var symbol = symbolValueOf(this);
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var string = symbolToString(symbol);
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if (hasOwn(EmptyStringDescriptionStore, symbol)) return '';
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var desc = NATIVE_SYMBOL ? stringSlice(string, 7, -1) : replace(string, regexp, '$1');
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return desc === '' ? undefined : desc;
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}
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});
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$({ global: true, constructor: true, forced: true }, {
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Symbol: SymbolWrapper
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});
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}
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