The latest version of once is 0.4-0.
once
Version 0.3 revision 0 uploaded by DmitryBogatov.
Package meta
- 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- Author
- Dmitry Bogatov
- Bug reports
- n/a
- Category
- Data
- Copyright
- 2015-2018 Dmitry Bogatov
- Homepage
- https://gitlab.com/kaction/haskell-once
- Maintainer
- KAction@debian.org
- Package URL
- n/a
- Stability
- n/a