06-put-it-together.ts

interface User {
  readonly id: number;
  readonly name: string;
  readonly wifeName: string;
  readonly parents: ReadonlyArray<string>;
}

const user: User = {
  id: 1,
  name: "John",
  wifeName: "Mary",
  parents: ["George", "Maria"]
};

user = {}; // Cannot assign to 'user' because it is a constant.
user.id = 2; // Cannot assign to 'id' because it is a read-only property.
user.wifeName = 'Hermione'; // Cannot assign to 'wifeName' because it is a read-only property.
user.parents = []; // Cannot assign to 'parents' because it is a read-only property.
user.parents.push("Thor"); // Property 'push' does not exist on type 'readonly string[]'.