Object.getPrototypeOf()

Baseline

20157

Object.getPrototypeOf() ( [[Prototype]] )

const prototype = {};
const object = Object.create(prototype);

console.log(Object.getPrototypeOf(object) === prototype);
// : true

Object.getPrototypeOf(obj)

obj

null

getPrototypeOf

const proto = {};
const obj = Object.create(proto);
Object.getPrototypeOf(obj) === proto; // true

ES5 obj TypeError ES2015 Object

Object.getPrototypeOf("foo");
// TypeError: "foo" is not an object (ES5 code)
Object.getPrototypeOf("foo");
// String.prototype                  (ES2015 code)


ECMAScript 2027 LanguageSpecification # sec-object.getprototypeof

Object.getPrototypeOf (core-js)
es-shims Object.getPrototypeOf
Object.prototype.isPrototypeOf()
Object.setPrototypeOf()
Object.prototype.__proto__
Reflect.getPrototypeOf()
Object.getPrototypeOf (John Resig, 2008)

MDN

MDN 2025823

GitHub

Object
1. Object()
1. __proto__
2. constructor
Object/Function
1. __proto__
2. constructor