[Haskell-cafe] FiniteMap-like module for unordered keys?

Is there a module that provides functionality similar to that of Data.FiniteMap for keys that do not have a defined ordering relation? (I looked at Data.HashTable, but I couldn't figure why it needs to be implemented in the IO monad, except to optimize the internal implementation. Also, it's not clear to me how it behaves when a key is inserted that already exists.) #g ------------ Graham Klyne For email: http://www.ninebynine.org/#Contact