Factory

• Use a factory to instantiate new objects (instead of the new keyword)

class IOSButton {}

class AndroidButton {}

// Without Factory
const button1 = os === "ios" ? new IOSButton() : new AndroidButton();
const button2 = os === "ios" ? new IOSButton() : new AndroidButton();

class ButtonFactory {
  createButton(os: string): IOSButton | AndroidButton {
    if (os === "ios") {
      return new IOSButton();
    } else {
      return new AndroidButton();
    }
  }
}

// With Factory
const factory = new ButtonFactory();
const btn1 = factory.createButton(os);
const btn2 = factory.createButton(os);