well-known-symbol.js 777 B

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  1. var global = require('../internals/global');
  2. var shared = require('../internals/shared');
  3. var hasOwn = require('../internals/has-own-property');
  4. var uid = require('../internals/uid');
  5. var NATIVE_SYMBOL = require('../internals/symbol-constructor-detection');
  6. var USE_SYMBOL_AS_UID = require('../internals/use-symbol-as-uid');
  7. var Symbol = global.Symbol;
  8. var WellKnownSymbolsStore = shared('wks');
  9. var createWellKnownSymbol = USE_SYMBOL_AS_UID ? Symbol['for'] || Symbol : Symbol && Symbol.withoutSetter || uid;
  10. module.exports = function (name) {
  11. if (!hasOwn(WellKnownSymbolsStore, name)) {
  12. WellKnownSymbolsStore[name] = NATIVE_SYMBOL && hasOwn(Symbol, name)
  13. ? Symbol[name]
  14. : createWellKnownSymbol('Symbol.' + name);
  15. } return WellKnownSymbolsStore[name];
  16. };