eff
fusedeffects
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eff  fusedeffects  

16  3  
523  597  
1.7%  0.8%  
0.8  7.0  
over 2 years ago  about 2 months ago  
Haskell  Haskell  
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eff

[ANNOUNCE] GHC 9.6.1 is now available
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.

Effectful  PaweÅ‚ Szulc  Lambda Days 2022
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/.

Looking for languages that combine algebraic effects with parallel execution
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.

Should I pick up OCaml or Haskell?
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 â€” 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)

[ANN] cleff  fast and consise extensible effects
cleff's Eff monad is esentially implemented as a ReaderT IO. [...] This is first done by eff, [...]

Opinions on Reader + Continuationbased IO?
Here is link number 1  Previous text "eff"
This is essentially how continuation based effect systems work, check out eveff and eff.

Where's more discussion of the designs of effect systems?
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 fusedeffects and polysemy, but they turned out to have some weird semantics. eff is her effort to fix that.
While her eff is still under construction, there are relative more mature pieces like Koka etc. I'd very much like to understand how her concerns map to those other effect systems, but can't find more writeups about the design space of effect systems.

The Problem of Effects (2020)
Let me tell you what I'm worried about with effects systems: One of the smartest people I know of has a library called Eff https://github.com/hasura/eff that efficiently implements effects through some modifications to GHC. The thing is, she's pretty much stopped working on because she found some really nasty semantic edgecases that she couldn't resolve to her satisfaction. (I don't understand the problems well enough to describe them, and I think they're specific to lazy languages, but it has left me cautious about the effect model in general.)
fusedeffects

Where's more discussion of the designs of effect systems?
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 fusedeffects and polysemy, but they turned out to have some weird semantics. eff is her effort to fix that.
 Haskell doesn't make sense without pure functions
 Monthly Hask Anything (June 2021)
What are some alternatives?
polysemy  :gemini: higherorder, noboilerplate monads
eveff  Efficient Haskell effect handlers based on evidence translation.
frpzoo  Comparing many FRP implementations by reimplementing the same toy app in each.
freersimple  A friendly effect system for Haskell
controlmonadfree  Free monads and monad transformers
extensibleeffects  Extensible Effects: An Alternative to Monad Transformers
machines  Networks of composable stream transducers
ChannelT  Generalized stream processors
abstractpar
inotherwords  A higherorder effect system where the sky's the limit
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