eff VS mtl-style-example

Compare eff vs mtl-style-example and see what are their differences.


🚧 a work in progress effect system for Haskell 🚧 (by hasura)


A small example of using mtl style to unit test effectful code (by lexi-lambda)
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eff mtl-style-example
17 2
528 106
0.9% -
0.0 0.0
28 days ago over 5 years ago
Haskell Haskell
ISC License ISC 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.


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 2023-05-08.


Posts with mentions or reviews of mtl-style-example. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2023-03-17.
  • Haskell ecosystem questions.
    5 projects | reddit.com/r/haskell | 17 Mar 2023
    Re: effects libraries, it's probably worth starting with e.g. https://www.fpcomplete.com/blog/2017/06/readert-design-pattern/ https://www.parsonsmatt.org/2018/03/22/three_layer_haskell_cake.html https://github.com/lexi-lambda/mtl-style-example if you're just getting familiar with the ecosystem. I'll add, anything written by the the people I linked to in this comment is probably worth reading as well.
  • I’ve tried to learn Haskell several times. But keep failing
    8 projects | reddit.com/r/haskell | 1 Jun 2021
    Personally, it felt to me like, once I really understood monad transformers (https://hackage.haskell.org/package/transformers) and mtl (https://hackage.haskell.org/package/mtl), the reasons they both exist and how they are distinct, how you use them generally and what common patterns are around structuring your app (see e.g. https://github.com/lexi-lambda/mtl-style-example and the 3-layer-cake link someone else provided here for two), a lot of stuff in the ecosystem suddenly became comprehensible and useful to me, in a practical, "real world" way. In fact I'd go so far as to assert that getting comfortable with mtl in particular is the biggest single step you can take to being able to build arbitrarily useful real-world apps that are no longer toys.

What are some alternatives?

When comparing eff and mtl-style-example you can also consider the following projects:

fused-effects - A fast, flexible, fused effect system for Haskell

frp-zoo - Comparing many FRP implementations by reimplementing the same toy app in each.

freer-simple - A friendly effect system for Haskell

extensible-effects - Extensible Effects: An Alternative to Monad Transformers

in-other-words - A higher-order effect system where the sky's the limit

polysemy - :gemini: higher-order, no-boilerplate monads

ihp - 🔥 The fastest way to build type safe web apps. IHP is a new batteries-included web framework optimized for longterm productivity and programmer happiness

pcre2 - Complete Haskell binding to PCRE2

hoogle - Haskell API search engine

ponyc - :horse: Pony is an open-source, actor-model, capabilities-secure, high performance programming language

eveff - Efficient Haskell effect handlers based on evidence translation.

envy - :angry: Environmentally friendly environment variables