mohamed-gara

import {Customer} from './customer';
import {Order} from './order';

export class OrderDiscounter {
   constructor(public customer: Customer, public order: Order) {}
   
   discountedAmount() {
     return (100 - this.customer.discount()) * this.order.amount;
   }
}

mohamed-gara

export class Order {
   constructor(public amount: number) {}
}

mohamed-gara

import {Order} from './order';

export class Customer {
  
  constructor(public orders: Order[]) {} 

  discount() {
    if (this.orders.length > 5) {
      return 10;
    } else {

mohamed-gara

import {DiscountCalculator, Order} from './order';

export class Customer implements DiscountCalculator {
  
  constructor(private orders: Order[]) {} 

  discount() {
    if (this.orders.length > 5) {
      return 10;
    } else {

mohamed-gara

export class Order {
   
   constructor(private discount: DiscountCalculator, private amount: number) {}

   discountedAmount() {
     return (100 - this.discount.discount()) * this.amount;
   }
}

export interface DiscountCalculator {

mohamed-gara

import {Customer} from './customer';

export class Order {

   constructor(private customer: Customer, private amount: number) {}

   discountedAmount() {
     return (100 - this.customer.discount()) * this.amount;
   }
}

mohamed-gara

import {Order} from './order';

export class Customer {
  
  constructor(private orders: Order[]) {} 

  discount() {
    if (this.orders.length > 5) {
      return 10;
    } else {

mohamed-gara

const customerOrders = findOrdersBy(customerId); // instead of findOrdersByCustomer(customerId)
const userOrders = findOrdersBy(creatorId); // instead of findOrdersByCreator(creatorId)

mohamed-gara

function findOrdersBy(customerId: CustomerId): Order[];
function findOrdersBy(creatorId: UserId): Order[];
function findOrdersBy(id): Order[] {
    ...
}

mohamed-gara

export function findOrdersBy(customerId: string): Order[] {
    ...
}