A 'vanilla' Scala implementation using OO and FP concepts.

OO: Used for dependency management.

FP: Same input results in same output, also higher-order functions. Side-effects, notably the console, are abstracted but not managed using as effects.

Worthwhile in this implementation

• The tests:
  • RockPaperScissorsCliSuite was written from a behavior perspective simulating 'end to end' interaction with the console. A goal here is to have a test that is relatively stable when the implementation would change.

Note, not implemented:

• Advanced computer logarithm. The current one just implements generates a random 'hand'.
  • For more advanced logic the previous outcomes and 'hands' can be passed.
    • The function () => Option[Hand] would turn into something like List[Outcome] => Option[Hand], where Outcome also contains the moves played by both players.

This implementation uses scala-cli. A nix flake is setup to setup the required environment.

Run:

scala-cli run .

Test (watching file changes):

scala-cli test -w .

IDE:

Running either of above commands generates project file for IntelliJ IDEA (bsp) and Metals (e.g. in VSCode).