1 var DESCRIPTORS = require('../internals/descriptors');
2 var defineProperty = require('../internals/object-define-property').f;
4 var FunctionPrototype = Function.prototype;
5 var FunctionPrototypeToString = FunctionPrototype.toString;
6 var nameRE = /^\s*function ([^ (]*)/;
9 // Function instances `.name` property
10 // https://tc39.es/ecma262/#sec-function-instances-name
11 if (DESCRIPTORS && !(NAME in FunctionPrototype)) {
12 defineProperty(FunctionPrototype, NAME, {
16 return FunctionPrototypeToString.call(this).match(nameRE)[1];