eff
🚧 a work in progress effect system for Haskell 🚧 (by hasura)
freer-simple
A friendly effect system for Haskell (by lexi-lambda)

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eff | freer-simple | |
---|---|---|
18 | 2 | |
553 | 231 | |
0.2% | 0.9% | |
0.0 | 0.0 | |
almost 2 years ago | 9 months ago | |
Haskell | Haskell | |
ISC License | BSD 3-clause "New" or "Revised" License |
The number of mentions indicates the total number of mentions that we've tracked plus the number of user suggested alternatives.
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
eff
Posts with mentions or reviews of eff.
We have used some of these posts to build our list of alternatives
and similar projects. The last one was on 2023-07-12.
-
Haskellers who moved to Rust: What has been your experience?
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.
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What are the current hot topics in type theory and static analysis?
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.
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[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.
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Effectful | Paweł 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/.
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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.
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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 — 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)
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[ANN] cleff - fast and consise extensible effects
cleff's Eff monad is esentially implemented as a ReaderT IO. [...] This is first done by eff, [...]
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Opinions on Reader + Continuation-based IO?
Here is link number 1 - Previous text "eff"
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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 fused-effects and polysemy, but they turned out to have some weird semantics. eff is her effort to fix that.
-
Languages that don't support Error-Catching as a Control Structure?
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).
freer-simple
Posts with mentions or reviews of freer-simple.
We have used some of these posts to build our list of alternatives
and similar projects. The last one was on 2021-06-27.
-
A solid GUI Framework for Haskell?
Why do you need a GUI library, if you can write your application using extensible effects frameworks, just choose any and enjoy!
- Monthly Hask Anything (June 2021)
What are some alternatives?
When comparing eff and freer-simple you can also consider the following projects:
frp-zoo - Comparing many FRP implementations by reimplementing the same toy app in each.
extensible-effects - Extensible Effects: An Alternative to Monad Transformers
eveff - Efficient Haskell effect handlers based on evidence translation.
streamproc - Haskell library providing a continuation-based stream processor arrow
fused-effects - A fast, flexible, fused effect system for Haskell
polysemy - :gemini: higher-order, no-boilerplate monads
in-other-words - A higher-order effect system where the sky's the limit
cond - Basic conditional operators with monadic variants.
mtl-style-example - A small example of using mtl style to unit test effectful code
freer-effects - An implementation of "Freer Monads, More Extensible Effects".

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Nutrient - The #1 PDF SDK Library
Bad PDFs = bad UX. Slow load times, broken annotations, clunky UX frustrates users. Nutrient’s PDF SDKs gives seamless document experiences, fast rendering, annotations, real-time collaboration, 100+ features. Used by 10K+ devs, serving ~half a billion users worldwide. Explore the SDK for free.
nutrient.io
featured