Write more understandable Haskell.

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LTS Haskell 22.29:
Stackage Nightly 2024-07-21:
Latest on Hackage:

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MIT licensed
Maintained by Taylor Fausak
This version can be pinned in stack with:flow-,1305

Module documentation for

Depends on 1 package(full list with versions):


Workflow Hackage Stackage

Write more understandable Haskell.

Flow is a package that provides functions and operators for writing more understandable Haskell. It is an alternative to some common idioms like ($) for function application and (.) for function composition.


Flow requires a Haskell compiler. It is tested with recent versions of GHC, but older or different compilers should be acceptable. For installation with Cabal, Flow requires at least Cabal 2.2.


To add Flow as a dependency to your package, add it to your Cabal file.

build-depends: flow ==2.0.*


Flow is designed to be imported unqualified. It does not export anything that conflicts with the base package.

import Flow

Cheat sheet

Flow Base
x |> f x & f
f <| x f $ x
apply x f f x
f .> g f >>> g
g <. f g . f
compose f g x g (f x)
x !> f -
f <! x f $! x
apply' x f seq x (f x)

Converting existing code

If you want to uniformly use flow operators you can use HLint with the hlint-flow.yaml file. For easy use, it is best to extract the hlint-flow.yaml to your project directory and do

> hlint -h hlint-flow.yaml <source file>


> hlint --git -h hlint-flow.yaml

to check all Haskell source tracked by git.

For more information about Flow, please read the Haddock documentation.


Change log

Flow follows the Package Versioning Policy. You can find release notes on GitHub.