immutable object

//cara 1
let object1 = {"nama" : "nasution", "alamat": "mikuasi"};
let object2 = Object.assign({},object1);
console.log(object2); //{ nama: "nasution", alamat: "mikuasi" }
object2.nama = "juliar";
console.log(object2); //{ nama: "juliar", alamat: "mikuasi" }
console.log(object1); //{ nama: "nasution", alamat: "mikuasi" }

//cara 2
let object3 = {"nama" : "nasution", "alamat": "mikuasi"};
let object4 = {...object3};
console.log(object4); //{ nama: "nasution", alamat: "mikuasi" }
object4.nama = "juliar";
console.log(object4); //{ nama: "juliar", alamat: "mikuasi" }
console.log(object3); //{ nama: "nasution", alamat: "mikuasi" }