On Thu, Jan 27, 2005 at 12:53:24PM -0500, S. Alexander Jacobson wrote:
This code gives me a Kind error because IVal isn't applied to enough type arguments.
import qualified Set
class Table table indexVal | indexVal->table where --insertIndex::item->indexVal item -> table item ->table item union::table item -> table item -> table item --union t1 t2 = t1
data DBTable item = DBTable data IVal item = Name item
instance Table DBTable (IVal ) where
Weirdly, when I uncomment the insertIndex function, things work.
That's because Haskell has to commit to some kind for indexVal and without any hits it chooses kind *. You can explicitly state the kind of indexVal. class Table table (indexVal :: * -> *) | indexVal->table where I can't help you with the other problem. The Main.$dmunion name in the message is indeed scary. Best regards, Tomasz