Playing around with System.Posix.Terminal, I realized that there are no Read, Show, Eq, Enum, ... instances for the data types defined there (TerminalState, TerminalMode, ...). This is not a very difficult problem to solve in one's own program, but it's not very handy, either. This raises a general question: What instances should be defined in the standard libraries for types like this? A general policy would be a good thing. IMHO, at least Read, Show, Typeable and Eq could be expected, having Ord, Enum and Bounded, too, would be nice. Any opinions? Cheers, S.