Eff interpreter implementation for atnos-eff last action

Abstract

Eff from atnos-eff has a function addLast which allows us to register the side-effects we want to execute at the end. But I think the implementation has some issues:

1. This feature is probably NOT described original paper
   • so we cannot find out what is the right behavior of this😇
2. And this can be done by the original Eff idea without special modification for Eff data structure
3. In atnos-eff, last of Eff is handled like try-catch-finally logic of MonadError but
   • the last logic is not the same of try-catch-finally because the last logic should be actually done in the last if some Effs are flatmapped
   • on the other hand, the error handling should be able to be applied to a specific Eff data, and it doesn't need to be done in the final

This repository is a PoC of (2).

Discussions are very welcome. Thank you for the reading!

How to use

You can try it out by the following command.

./sbt test

Acknowledgments

I would like to thank @halcat0x15a and @xuwei-k for many advices. But if there could be any mistakes in this repository, they were nothing to do with that.