hydraulics.cabal

name:                hydraulics
version:             1.0.0
synopsis:            Lift any pure function over any Applicative stack.
description:
  This package contains a family of functions based on familiar 'Applicative',
  'Functor', 'Traversable', and 'Foldable' methods but with the ability
  to operate on stacks of arbitrary depth.
  .
  For example, 'liftAll' is like the 'liftA2' and 'liftA3' functions except that it can lift a
  function through multiple layers of @Applicative@s instead of just one. Additionally,
  it can lift a function of arbitrary arity, not just a 2 argument function like with 'liftA2'.
  .
  The term \"stack\" is used in this library's documentation to refer
  to something like
  .
  > Maybe [Either Bool [Int]]
  .
  where @Int@ is embedded in a nesting of types that all share some common
  interface, such as @Applicative@, @Traversable@, or @Foldable@.
  .
  It's necessary to turn on <https://gitlab.haskell.org/ghc/ghc/wikis/type-application TypeApplications>
  so that you can supply a type argument that tells the compiler about the stack you are operating on.
  You specify the stack by giving it's type with @()@ as the embedded value. The @()@ should be at the level
  in the stack at which your target value is embedded.
  Here is an example GHCi session:
  .
  >>> :set -XTypeApplications
  >>> liftAll @[Maybe [()]] (+) [Just [3 :: Int]] [Just [6, 7]]
  [Just [9,10]]

  >>> data Foo = Foo Int String Double deriving Show
  >>> liftAll @[[()]] Foo [[2]] [["string"]] [[5]]
  [[Foo 2 "string" 5.0]]

  >>> fmapAll @[Maybe ()] length [Just "string"]
  [Just 6]

  >>> traverseAll @(Either String [()]) print (Right [1,2,3])
  1
  2
  3
  Right [(),(),()]
  .
  (Additional examples are in the haddocks.)
homepage:            https://github.com/aaronallen8455/hydraulics#readme
license:             BSD3
license-file:        LICENSE
author:              Aaron Allen
maintainer:          aaronallen8455@gmail.com
copyright:           2020 Aaron Allen
category:            Control, Utils
build-type:          Simple
extra-source-files:  README.md
cabal-version:       >=1.10

library
  hs-source-dirs:      src
  exposed-modules:     Control.Lift
  build-depends:       base >= 4.7 && < 5
  default-language:    Haskell2010

source-repository head
  type:     git
  location: https://github.com/aaronallen8455/hydraulics