Dear people,
i cannot tell, whether the following is a particular implementation
bug or it is against Haskell-98:
class Rs r where toRs :: r a -> a -> r a
data (Num a) => Rsi a = Rsi a a
data (Integral a) => Rse a = Rse a a
instance Rs Rsi where toRs (Rsi _ b) a = Rsi (a-b) b
instance Rs Rse where toRs (Rse _ b) a = Rse (rem a b) b
It wants to say, that toRs implements differently for several
constructors.
As Rsi is declared to presume the Num a context,
has Haskell to accept `a-b' in the instance for Rsi ?
If it has not, then this reduces the language expressiveness ...
How to fix this?
Thank you in advance.
------------------
Sergey Mechveliani
[EMAIL PROTECTED]
