Subject: haskell type classing · Posted: 2006-02-08, 03:37am
Rank: ? (4)
Member #: 26601
Aight, I'm trying teach myself how to write my own classes in haskell and I came upon an error recently and cant seems to figure out how to fix it. Can anyone help???
My Script so far says:
Code:
module Lab2 where
class Null a where
nullify :: a -> a
instance Null Int where
nullify x = 0
and when i run it hugs I get an error that says"
"Hugs session for:
C:\Program Files\Hugs98\lib\Prelude.hs
C:\Documents and Settings\04044465\Desktop\lab2.hs
Lab2> nullify 10
ERROR - Unresolved overloading
*** Type : (Num a, Null a) => a
*** Expression : nullify 10 "
Now please do not link me to the tutorial on haskell.org, cuz i know what I'm doing I just can't figure this bit out. Please someone help........
