On Tue, May 02, 2006 at 12:57:17AM +0200, Johan Henriksson wrote:
toBinary :: a -> [Int] -- pack data as a string of bytes fromBinary :: [Int] -> a -- unpack binarySize :: a -> Maybe Int -- number of bytes for this type or Nothing if not fixed
the packing would be compiler dependent since it is not of interest to read the content, just to get an easy way of marshalling arbitrary types.
Depending on what you mean, we might already have this, or it might be impossible in general :) if you just want to create a reference to an arbitrary haskell type that you can pass to foreign code, and then recover the original haskell value from, then the Foreign.StablePtr does just this. it lets you cast haskell values to plain pointers and back again. if you want to store the structure in memory, then the Storable class provides this. I have thought it would be useful to allow deriving(Storable) with the obvious meaning and adding a 'StorableRef' that can create a reference to an arbitray storable object. I believe bulat is working on unboxed arrays that can work like this. of course, the limitation is that your data types need to be in class Storable. since you don't seem to care about compiler independence and if you are willing to give up architecture independence, you can probably use storable to serialize structures to disk, but do so at your own risk. pretty much any solution will require a typeclass to guide and restrict it, otherwise how would the compiler handle function types? it can't serialize the body of functions in general, or handle cyclic structures or pointers from the serialized version to live haskell structures and how they interect with the GC? You also might want to look at the various Binary libraries out there. perhaps one fits your needs. John -- John Meacham - ⑆repetae.net⑆john⑈