Reflect.setPrototypeOf()

The static Reflect.setPrototypeOf() method is the same method as Object.setPrototypeOf(), except for its return type. It sets the prototype (i.e., the internal [[Prototype]] property) of a specified object to another object or to null, and returns true if the operation was successful, or false otherwise.

Syntax

Reflect.setPrototypeOf(target, prototype)

Parameters

target: The target object of which to set the prototype.
prototype: The object's new prototype (an object or null).

Return value

A Boolean indicating whether or not the prototype was successfully set.

Exceptions

A TypeError, if target is not an Object or if prototype is neither an object nor null.

Description

The Reflect.setPrototypeOf method changes the prototype (i.e. the value of the internal [[Prototype]] property) of the specified object.

Examples

Using Reflect.setPrototypeOf()

Reflect.setPrototypeOf({}, Object.prototype)  // true

// It can change an object's [[Prototype]] to null.
Reflect.setPrototypeOf({}, null)  // true

// Returns false if target is not extensible.
Reflect.setPrototypeOf(Object.freeze({}), null)  // false

// Returns false if it cause a prototype chain cycle.
let target = {}
let proto = Object.create(target)
Reflect.setPrototypeOf(target, proto)  // false

Specifications

Specification
ECMAScript Language Specification (ECMAScript) # sec-reflect.setprototypeof

Browser compatibility

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