Johannes Waldmann wrote:
Georg made the point that if a type is an instance of Show, then it should also be an instance of Read, and read . show == id
That does (hopefully) happened now.
I'd like to repeat my earlier point that it would be better if the user of the type can decide whether he wants some predefined Show/Read instances or roll his own.
It is really not an option (in current Haskell) to put Show/Read instances in a separate module. Just consider if you want to combine a couple of module were two modules rely on different instance implementations. (A horror if you want to share code) IT is, however, an option to add auxiliary (non-overloaded) utility functions for showing and reading (parameterized of some separators). Cheers Christian