Echte Laufzeitkapselung mit ECMAScript-Private-Fields

class BankAccount {
  #balance: number;
  public readonly accountId: string;
 
  constructor(accountId: string, initialDeposit: number) {
    this.accountId = accountId;
    this.#balance = initialDeposit;
  }
 
  public deposit(amount: number): void {
    if (amount <= 0) throw new Error("Deposit amount must be positive");
    this.#balance += amount;
  }
 
  public getBalance(): number {
    return this.#balance;
  }
}