[Haskell-cafe] GHC optimisations

[Twan van Laarhoven]

Brandon S. Allbery KF8NH wrote:

> 
> On Aug 21, 2007, at 22:13 , Twan van Laarhoven wrote:
> 
>> Other rules that could be interesting are:
>> > forall a b. fromInteger a + fromInteger b = fromInteger (a + b)
> 
> 
> I don't think this will work, a and b have to be the same type.

They are of the same type, both are Integers,

 > forall a b :: Integer.
 >     ((fromInteger (a::Integer)) + (fromInteger b)) :: Num n => n
 >   =
 >     (fromInteger (a + b :: Integer)) :: Num n => n

Twan