Christian Maeder
So please, please, please, if you decide to use a newtype, do /not/ hide the constructor.
The better alternative to "not hiding the constructor" is to supply conversion functions that may or may not do more than the constructor and selector and are named accordingly. (This just disallows pattern matching.)
Except annoying library users, what would be the point of that? Please understand that as a middle level developer (abstractions, protocol implementations, frameworks, etc.) I am sometimes annoyed by the idealism of some library interfaces, and I find myself reinventing the wheel very often, because the closed interfaces of some existing libraries just don't support what I need, even though the technical basis would be there, or because of the abstraction forest I'm unable to guarantee or even get good performance. I could totally understand having a black box interface for some higher level stuff, but ByteString is still low/middle level and should support me as a developer on that level. Unifying vector and bytestring sounds like a great step, and I would find it ruined already by wrapping it up in a newtype. Hiding the constructor would make this even worse. Greets, Ertugrul -- nightmare = unsafePerformIO (getWrongWife >>= sex) http://ertes.de/