How can an object overwrite itself using setter?

September 7, 2022

I want an object to overwrite itself using a setter. Unfortunately it does not work with my script. Probably it is because "this" cannot stand alone. Is there another way to solve this?

class myClass {
  set updateObj(value) {
    this = value // how to overwrite the object itself? "this" doesn't work ..
  }
}

let myObject = new myClass()
const test = (myObject.updateObj = { foo: "bar" })

console.log(test)

>Solution :

No an instance cannot replace itself.

But you can merge some data with properties into this with Object.assign.

class myClass {
  set updateObj(value) {
    Object.assign(this, value)
  }
}

let myObject = new myClass()
myObject.updateObj = { foo: "bar" }
console.log(myObject)

myObject.updateObj = { foo: "baz" }
console.log(myObject)