eff VS haskell.nix

You can swap-out implementations for testing, avoid the crazy N^2 instances issues, etc. They're pretty cool. Currently there are many competing libraries. polysemy and eff both have good examples on their homepages.

Effect systems and Algebraic effects. ocaml has just released a stripped-down effect system. People are also working on Effect systems for Haskell (eff, fused-effects, effet). Koka is a language built with effects first and foremost and it’s rapidly gaining popularity. Unison also has effects.

There are also a few subtle issues that arise with delconts related to semantics of higher order effects (see here and here), but they might be solvable.

Details are in https://github.com/hasura/eff/issues/12 and https://www.reddit.com/r/haskell/comments/pywuqg/unresolved_challenges_of_scoped_effects_and_what/.

You'll get fearless parallel with STM in the mixture, and GHC is getting a work in progress effect system for Haskell, as Delimited continuation primops has been merged.

My last example is algebraic effects, some of which have been made possible in a both practical and efficient way thanks to extremely recent research, and that I can use to implement architectures like Ports and Adapters or Clean Architecture and have very maintainable code. (Extensible Effects — An Alternative to Monad Transformers was published in 2013, Effect Handlers in Scope was published in 2014 and they are behind Polysemy, while there is ongoing work on effects with even better performance, like Eff)

cleff's Eff monad is esentially implemented as a ReaderT IO. [...] This is first done by eff, [...]

Here is link number 1 - Previous text "eff"

Languages such as Koka only support algebraic effects, not scoping operations such as catch and listen. The Effect Handlers in Scope paper introduces scoping operations, which lead to the Haskell libraries fused-effects and polysemy, but they turned out to have some weird semantics. eff is her effort to fix that.

There are a few languages that have algebraic effect systems, most notably Haskell, but these systems are implemented as libraries, not baked into the language (which can have advantages and disadvantages).

I'm not a great haskeller but I found haskell.nix better for Haskell projects, like the commenter on Discourse suggested. I've had a few issued regarding package versions with nixpkgs that haskell.nix solved.

FWIW, there's also libraries like haskell.nix that solve the caching problem.

I would try haskell.nix.

If you want to hurt your brain, check out haskell.nix. That's some good stuff right there ^^

The haskell.nix framework is good for this.

One cool thing is that this will enable GHC builds using ucrt instead of vscrt in the future. Concretely, together with NixOS/nixpkgs#171418 and its follow-up NixOS/nixpkgs#173498), this will e.g. allow haskell.nix to upgrade to a newer wine pin for TH cross compilation: https://github.com/input-output-hk/haskell.nix/blob/dd13e822529ae5342494969bce8a457522a60100/overlays/wine.nix

I've been using IOHK's alternative infrastructure for this reason. It has its quirks but I've been happier with it. Before that I think I was using developPackage from the nixpkgs haskell tooling which had some introspection ability. You may consider trying that out. But as I remember this will not abide by your version bounds.

There's a lot to like here. Alas, despite minimal dependencies, terminfo is somehow uniquely problematic in haskell.nix.

If you are somewhat comfortable with nix: https://github.com/input-output-hk/haskell.nix supports GHCJS 8.10.x (in particular 8.10.7).