Hello Brian, Thursday, November 2, 2006, 12:15:38 AM, you wrote:
In particular, I think having features like : import M1 hiding (instance C T) and module M hiding (instance C T) would eliminate the need for special-case handling of derived instances (if two imported modules happen to derive the same instances, you can just hide the instances from one of them). Instance hiding is an important feature in its own right.
i vote for this feature too. in my AltBinary library, there are many different ways to serialize strings, for example. i want to provide default "instance Binary String" for quick&dirty use and ability to hide just this instance in the case when user need to overwrite it. now i forced to put all instance declarations in separate file and suggest user to copy this file into his project and make appropriate edits! also, expicit instance imports was in prewvious Haskell versions. so i think it will be great to use implicit importing of all instances by default but allow to hide all instances or specific instance and import just the instance required: import M (instance Binary String) -- hides all other Binary instances module M hiding (instance Binary) -- hides all Binary instances -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com