Comments on: Wrapping IO, part 1

By: therning.org/ magnus » Blog Archive » Strachey, referential transparency, Haskell

Sun, 05 Aug 2012 04:22:51 +0000

[...] in Haskell it’s possible to make subsets of IO (by wrapping IO, see e.g. my own posts on wrapping IO, part 1 and wrapping IO, part 2). I’m sure that if including the world in the environment is the way [...]

By: Magnus

Magnus — Tue, 08 Sep 2009 20:56:31 +0000

Jean-Denis, cool, and good to know for the future, though it’s hardly good for understanding

By: Jean-Denis Koeck

Jean-Denis Koeck — Tue, 08 Sep 2009 16:38:35 +0000

You can derive the monad instance like this:

{-# LANGUAGE GeneralizedNewtypeDeriving #-}

newtype HideIO a = HideIO { runHideIO :: IO a }
    deriving(Monad)

By: sfvisser

sfvisser — Tue, 08 Sep 2009 07:01:39 +0000

Please check the 'jail' package on Hackage for another example of this kind of trickery.

By: therning.org/ magnus » Blog Archive » Wrapping IO, part 2

therning.org/ magnus » Blog Archive » Wrapping IO, part 2 — Mon, 07 Sep 2009 22:17:16 +0000

[...] Incoherent mumblings « Wrapping IO, part 1 [...]