[Haskell-cafe] Help me TH code.

Hi all, I want use TH write some function like below: data DataType = StringT | IntT | CharT parse :: [(String,DataType)] -> (TypeA, TypeB, ... TypeN) Example: parse [("string", StringT), ("001", IntT), ("c", CharT)] will return: ("string", 001, 'c') So how to use TH write 'parse' function? Thanks! -- Andy