So I have (or rather the user of my package has):
{-# LANGUAGE DeriveDataTypeable #-}
newtype Foo = Foo Int deriving (Read, Show, Typeable, Data, ...) someFoo = Foo Int
Note: * the `newtype` could be `data` -- if that would help. * this is _not_ a parameterised type, but a 'baked in' `Int`. * the data constr is named same as the type -- if that would help. I can ask for `typeOf someFoo` and get `Foo` OK. I can ask for `typeOf Foo` and get `Int -> Foo` OK. If I ask for `typeOf (typeOf someFoo)` I get `TypeRep`. `typeOf (show $ typeOf someFoo`) gets me `[Char]` (aka `String`) So far very logical, but not very helpful. What I want is to get the based-on type baked inside `someFoo` -- that is: `Int` (It would also be handy to get the name of the data constr, just in case it's different to the type.) Do I need to get into `deriving (..., Generic)` ? That looks like serious machinery! Thanks AntC