class Money {
  #amount;
  constructor(amount) { this.#amount = amount; }
  [Symbol.toPrimitive](hint) {
    if (hint === 'number') return this.#amount;
    if (hint === 'string') return `$${this.#amount}`;
    return `Money(${this.#amount})`;
  }
}
const m = new Money(42);
console.log(`${m}`, m + 8, m == 42);