[Haskell-cafe] Should "do 1" compile

[Claus Reinke]

if you want to go down that route:

    Prelude> let monadic m = m `asTypeOf` return undefined

    Prelude> :t monadic undefined
    monadic undefined :: (Monad m) => m a

    Prelude> :t monadic $ undefined >> return ()
    monadic $ undefined >> return () :: (Monad m) => m ()

    Prelude> :t monadic $ undefined >> [ () ]
    monadic $ undefined >> [ () ] :: [()]

    Prelude> :t monadic $ undefined >> [ undefined ]
    monadic $ undefined >> [ undefined ] :: [a]

btw, ghc says:

    Prelude> :t do undefined
    do undefined :: t t1

while hugs says:

    Hugs> :t do undefined
    do {...} :: Monad a => a b

claus