control-monad-free VS contravariant

Compare control-monad-free vs contravariant and see what are their differences.


Free monads and monad transformers (by pepeiborra)


Haskell 98 contravariant functors (by ekmett)
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control-monad-free contravariant
0 1
7 72
- -
0.0 3.1
over 1 year ago 7 months ago
Haskell Haskell
LicenseRef-PublicDomain GNU General Public License v3.0 or later
The number of mentions indicates the total number of mentions that we've tracked plus the number of user suggested alternatives.
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Posts with mentions or reviews of control-monad-free. We have used some of these posts to build our list of alternatives and similar projects.

We haven't tracked posts mentioning control-monad-free yet.
Tracking mentions began in Dec 2020.


Posts with mentions or reviews of contravariant. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2021-10-21.
  • Co-Applicative programming style
    2 projects | | 21 Oct 2021
    The operator also pops up in George Wilson's 2018 talk, Contravariant Functors: the Other Side of the Coin, along with (>*) and (*<) operators to help things along. Shortly after its publication, Issue #57 for contravariant was raised, suggesting not only (>*<) but the other operators from George's talk.

What are some alternatives?

When comparing control-monad-free and contravariant you can also consider the following projects:


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

mtl - The Monad Transformer Library

rio-orphans - A standard library for Haskell

freer-simple - A friendly effect system for Haskell

record - Anonymous records

transient - A full stack, reactive architecture for general purpose programming. Algebraic and monadically composable primitives for concurrency, parallelism, event handling, transactions, multithreading, Web, and distributed computing with complete de-inversion of control (No callbacks, no blocking, pure state)

distributed-closure - Serializable closures for distributed programming.

free - free monads

foldl - Composable, streaming, and efficient left folds

hdph - Haskell distributed parallel Haskell

capability - Extensional capabilities and deriving combinators