Brief: This is a story about a rookie alchemist to learn property testing in Elixir. If you are also a alchemist and want to know what’s property testing, welcome to share my experience. If you are not, in the first half of this story, there are some basic knowledges about property testing for your.

I begin to develop Java recently. I had been asked a question about the behavior super/sub class. And, it’s not quite the same as I thought. For example we have this Java program using derived class:

First is a very simple program to simulate requesting I/O in the main function.