cabal-version: 1.12

-- This file has been generated from package.yaml by hpack version 0.31.0.
--
-- see: https://github.com/sol/hpack
--
-- hash: 724ed4284796e6183f3e0d1d8985319bbd1d4aabedf6dbbf827b5973f884b38e

name:           once
version:        0.4
synopsis:       memoization for IO actions and functions
description:    Package provides single polymorphic function 'once', that allows you
                to memoize IO actions and functions, evaluating them at most once.
                .
                >>> let mkStamp = (putStrLn "stamping" >> writeFile "/tmp/stamp" "") :: IO ()
                >>> -- onceStamp :: IO ()
                >>> onceStamp <- once mkStamp
                >>> -- onceStamp actually evaluates mkStamp it wraps first time.
                >>> onceStamp
                stamping
                >>> -- but second time result `()' is memoized, no action is performed.
                >>> onceStamp
                >>> -- we can memoize functions too
                >>> foo <- once $ \x -> print "foo" >> print (x :: Int)
                >>> -- action will be performed once for every distinct argument
                >>> foo 10
                foo
                10
                >>> foo 10
                10
                >>> foo 4
                foo
                4
category:       Data
homepage:       https://gitlab.com/kaction/haskell-once
author:         Dmitry Bogatov
maintainer:     KAction@debian.org
copyright:      2015-2018 Dmitry Bogatov
license:        GPL-3
license-file:   LICENSE
build-type:     Simple

source-repository head
  type: git
  location: https://gitlab.com/kaction/haskell-once

library
  exposed-modules:
      Control.Once
  other-modules:
      Control.Once.Class
      Control.Once.Internal
      Control.Once.TH
      Paths_once
  hs-source-dirs:
      src
  build-depends:
      base >=4.7 && <5
    , containers >=0.5
    , hashable >=1.2
    , template-haskell >=2.10
    , unordered-containers >=0.2
  default-language: Haskell2010

test-suite spec
  type: exitcode-stdio-1.0
  main-is: Spec.hs
  other-modules:
      Paths_once
  hs-source-dirs:
      test
  ghc-options: -threaded -rtsopts
  build-depends:
      HUnit
    , async
    , base >=4.7 && <5
    , containers >=0.5
    , hashable >=1.2
    , hspec
    , once
    , template-haskell >=2.10
    , unordered-containers >=0.2
  build-tool-depends:
      hspec-discover:hspec-discover
  default-language: Haskell2010