Reflect.set()

const object = {};
Reflect.set(object, "foo", 42);

console.log(object.foo);
// : 42

const array = ["duck", "duck", "duck"];
Reflect.set(array, 2, "goose");

console.log(array[2]);
// : "goose"

Reflect.set(target, propertyKey, value)
Reflect.set(target, propertyKey, value, receiver)

target[propertyKey] = value;

// 
const obj = {};
Reflect.set(obj, "prop", "value"); // true
obj.prop; // "value"

// 
const arr = ["duck", "duck", "duck"];
Reflect.set(arr, 2, "goose"); // true
arr[2]; // "goose"

// 
Reflect.set(arr, "length", 1); // true
arr; // ["duck"]

// 1 "undefined" 
Reflect.set(obj); // true
Reflect.getOwnPropertyDescriptor(obj, "undefined");
// { value: undefined, writable: true, enumerable: true, configurable: true }

const target = {};
const receiver = {};
Reflect.set(target, "a", 2, receiver); // true
// target  {}; receiver  { a: 2 }

const target = { a: 1 };
const receiver = {};
Reflect.set(target, "a", 2, receiver); // true
// target  { a: 1 }; receiver  { a: 2 }

const target = {
  set a(v) {
    this.b = v;
  },
};
const receiver = {};
Reflect.set(target, "a", 2, receiver); // true
// target  { a: [Setter] }; receiver  { b: 2 }