trans-fx

This is the source repository of the trans-fx family of Haskell libraries, which together comprise an experimental effect framework based on monad transformer transformers.

trans-fx is a reimagining of monad transformers in the style of transformers and mtl taking advantage of some newer features of GHC. Our aim is to provide a composable, extensible, and mockable grammar of monadic effects that is efficient, easy to use, and robust enough for production systems.

Currently this is very much in progress and will only be of interest to the most intrepid functoristas. :)

The closest thing to documentation is this little tutorial.

trans-fx is split into a few separate libraries to help keep dependencies under control.

• trans-fx-core is the foundation of the effect system and depends only on base.
• trans-fx-io is a collection of simple effect layers using IO.
• trans-fx-data is a collection of specialized state effect layers with the semantics of common data structures.
• trans-fx-test includes helper code for writing tests: Arbitrary instances and lawful class tests.
• trans-fx-demo is a collection of tutorials on how to use and extend the library.