مولّد مخطط استدعاءات TypeScript

type Order = { id: number; items: { price: number }[] };

function loadOrders(userId: number): Summary[] {
  return fetchOrders(userId).map(normalize);
}

function fetchOrders(userId: number): Order[] {
  return [{ id: userId, items: [{ price: 12 }] }];
}

type Summary = { id: number; total: number };

function normalize(order: Order): Summary {
  return { id: order.id, total: computeTotal(order) };
}

function computeTotal(order: Order): number {
  return order.items.reduce((sum, item) => sum + item.price, 0);
}