On 15.09 21:53, Bulat Ziganshin wrote:
EK> data Packet = Packet Word32 Word32 Word32 [FastString]
well. you can see my own BinaryStream package at http://freearc.narod.ru
class BinaryData a where read :: ... write :: ...
I don't think this is a very good solution. Keeping the on-wire datatypes explicit makes sense to me. Also things like endianess will need to be taken into account. If the encoding is derived automatically then changing the Haskell datatype will change the on-wire representation. This is not wanted when interfacing with external protocols. For typeclasses I would rather have: getWord32BE :: Num a => MyMonad a than get :: MyClass a => MyMonad a Note the difference between the Haskell type determining the on-wire type and it being explicit. I already have working TH code for the case where I want to derive automatic binary serialization for Haskell datatypes (SerTH).
EK> Maybe even the tuple could be eliminated by using a little of TH.
it may be eliminated even without TH! :+: and :*: should work, although i don't tried this
I don't know how generics work in newer versions of GHC, but it may be worth investigating. - Einar Karttunen