types.ts

interface User {
  id: number
  name: string
  email: string
  createdAt: Date
}

class UserService {
  private users: User[] = []

  async createUser(userData: Omit<User, 'id' | 'createdAt'>): Promise<User> {
    const user: User = {
      ...userData,
      id: Date.now(),
      createdAt: new Date()
    }

    this.users.push(user)
    return user
  }
}