darcs patch: Control.Monad: +void :: f a -> f ()

Fri Jan 8 16:44:55 EST 2010 gwern0@gmail.com * Control.Monad: +void :: f a -> f () See http://hackage.haskell.org/trac/ghc/ticket/3292 Turns m a -> m (). Lets one call functions for their side-effects without having to get rid of their return values with '>> return ()'. Very useful in many contexts (parsing, IO etc.); particularly good for 'forkIO' and 'forM_', as they demand return types of 'IO ()' though most interesting IO functions return non-().