Feature Requests item #1333482, was opened at 2005-10-20 11:34 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=358032&aid=1333482&group_id=8032 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None Status: Open Priority: 5 Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: Supertyping of classes Initial Comment: see "Supertyping Suggestion for Haskell" [url]http://repetae.net/john/recent/out/supertyping.html[/url] example: [code] class Num a <= Group a where (+) :: a -> a -> a negate :: a -> a [/code] apart from multiple inheritance, it could work like this: [code] import Prelude hiding ((+),negate) import qualified Prelude ((+),negate) class Group a where (+) :: a -> a -> a negate :: a -> a instance Num a => Group a where (+) = (Prelude.+) negate = Prelude.negate [/code] - coeus_at_gmx_de ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=358032&aid=1333482&group_id=8032