Adapter

The main goal of the Adapter design pattern is to convert one interface to another interface. In the physical world, the best example of this idea would be an electrical plug adapter or a USB adapter.

Imagine yourself in a hotel room late in the evening, with 7% battery left on your phone. Your phone charger was left in the office at the other end of the city. You only have an EU plug charger with a Mini USB cable. But your phone uses USB-C, as you had to upgrade. You're in New York, so all of your outlets are (of course) USB-A. So, what do you do? Oh, it's easy. You look for a Mini USB to USB-C adapter in the middle of the night and hope that you have remembered to bring your EU to US plug adapter as well. Only 5% battery left – time is running out!

So, now that we understand what adapters are for in the physical world, let's see how we can apply the same principle in code.

Let's start with interfaces.

USPlug assumes that power is Int...