After gdcr18 my friend Rubén created a repository to implement the Game of life without using conditionals.
As he explained in his the README.md:
This repo is a small exercise I did after our last Global Day of Coderetreat in Madrid. We usually do a restriction based on no conditionals (ifs, switchs, ternary operators...).
This is usually a shocking restriction and it was for me the first time, but I wanted to take some time to do the whole kata without a conditional. And here it is.
After the session 4, Rubén told me that he had an idea to implement this without conditional and without any data structure.
Just after the event, when we arrived home he sent me the repo with the solution we have been commented in Kotlin. Since the only way to really understand and learn something is to try it by yourself. I grabbed the idea and write a solution in Java trying to avoid conditionals and data structures
I created two types of cells (AliveCell and DeadCell), with this two classes and avoid null points in the universe, the next step is to look for the neighbours.
To define the neighborhoods I tried to use the number of neighbours inside them, but after finishing the problem, I realized that a neighborhood without neighbour is the same that the one with two neighbours. Taking this into account I decided to use three categories (thanks Rubén for the idea):
- Unhealthy: Cell here will die
- WithoutEffects: Cell here will keep their state
- Healthy:
AliveCellwill keep alive andDeadCellwill come to life
After modeling the cells behavior with polymorphism I found a problem in the Universe while looking for the neighbours. Despite I avoid a position map to look for the neighbours I need it to classify the neighborhoods :sad:
After all I just need a map to know the type of neighborhood depending on the number of neighbours.
Note: I know a filter uses a conditional
- Test:
make test - Shell:
make liveshell - Run:
make run
If you want to test any specific case, you can modify the Main and run make run