UPDATE: I've worked this into a library in a private project, that abstracts over Free and CPS'd F for efficiency. If you'd be interested in using this, let me know and I can release a package.
An example Haskell implementation of the
"free transformers" approach to
building modular programs by composing layers of Free interpreters.
This was adapted from a combination of:
- http://mpickering.github.io/posts/2014-12-20-closed-type-family-data-types.html
- http://degoes.net/articles/modern-fp
- http://degoes.net/articles/modern-fp-part-2
- https://github.com/notxcain/onion-architecure
- https://gist.github.com/jdegoes/97459c0045f373f4eaf126998d8f65dc
In this example, the code does not (yet) go so far as to abstract over the
"computational context" (i.e. sequential/Free vs parallel/FreeAp) --
everything is currently sequential.
If you have any tips/ideas/fixes, please let me know!