var $ = require('../internals/export'); var getBuiltIn = require('../internals/get-built-in'); var hasOwn = require('../internals/has-own-property'); var toString = require('../internals/to-string'); var shared = require('../internals/shared'); var NATIVE_SYMBOL_REGISTRY = require('../internals/native-symbol-registry'); var StringToSymbolRegistry = shared('string-to-symbol-registry'); var SymbolToStringRegistry = shared('symbol-to-string-registry'); // `Symbol.for` method // https://tc39.es/ecma262/#sec-symbol.for $({ target: 'Symbol', stat: true, forced: !NATIVE_SYMBOL_REGISTRY }, { 'for': function (key) { var string = toString(key); if (hasOwn(StringToSymbolRegistry, string)) return StringToSymbolRegistry[string]; var symbol = getBuiltIn('Symbol')(string); StringToSymbolRegistry[string] = symbol; SymbolToStringRegistry[symbol] = string; return symbol; } });