I think your best bet is -fno-implicit-prelude, and defining
fromInteger = id :: Integer->Integer.
On Fri, Mar 20, 2009 at 10:06 AM, Lauri Oksanen
Hi,
Is there some way to tell ghc, how to interpret numeric literals? I would like it to interpret 1 as 1 :: Integer not 1 as fromInteger (1 :: Integer)
I have been playing with the following (rather ugly) code.
{-# OPTIONS -XFunctionalDependencies -XMultiParamTypeClasses -XTypeSynonymInstances #-} module Test where import Prelude(Integer, Double) import qualified Prelude as P default(Integer, Double)
type Z = Integer type R = Double
class Plus a b c | a b -> c where (+) :: a -> b -> c
instance Plus Z Z Z where j + k = j P.+ k instance Plus R R R where x + y = x P.+ y
instance Plus R Z R where x + j = x P.+ P.fromInteger j instance Plus Z R R where j + x = P.fromInteger j P.+ x
x = (1 :: Z) + (1.0 :: R) --y = 1 + 1.0
The commented line can't be compiled (because of ambiguous types, I think).
- Lauri _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe