Re: [Haskell-cafe] Functional dependence nightmare

26 Mar 2011


      On Saturday 26 March 2011 21:35:13, Edgar Gomes Araujo wrote:
...
Hi Stephen,
I've have done the following:
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE RankNTypes #-}
...
mbc :: forall a . (SubUnit a)=>[Point] -> SetActiveSubUnits a -> Box ->
StateMBC a [Unit a]
mbc p afl box = do
    cleanAFLs
    if (null afl)
        then do
            (unit, afl') <- case build1stUnit plane p1 p2 p of
                Just un  -> return (([un], fromList $ getAllSubUnits
un)::(SubUnit a)=>([Unit a], SetActiveSubUnits a))
Remove the context, that's given in the signature:

   return (([un], fromList ...) :: ([Unit a], SetActiveSubUnits a))
...
_        -> return ([]   , empty)
            analyze1stUnit unit afl'
.....
I hope that is right. Does it?

Re: [Haskell-cafe] Functional dependence nightmare

Daniel Fischer