readonly-props.ts

class Pizza {
  public toppings: string[] = [];

  constructor(readonly name: string) {}

  public addToping(topping: string) {
    this.toppings.push(topping);
  }
}

const pizza = new Pizza("Pepperoni");

pizza.addToping("Pepper");

console.log(`Pizza => ${JSON.stringify(pizza)}`);