On 26/10/2010, at 19:36, Bas van Dijk wrote:
How about:
malloc :: Storable a => IO (Ptr a) malloc = doMalloc Nothing where doMalloc :: Storable b => Maybe b -> IO (Ptr b) doMalloc dummy = mallocBytes (sizeOf dummy)
I don't think this will work because 'Maybe a' doesn't have a Storable instance.
Meh, it's late, just ignore me. This is what I was thinking while typing the above nonsense. You could redefine sizeOf and friends to take (Dummy a) instead of `a' as an argument and then use this: data Dummy a = Dummy malloc :: Storable a => IO (Ptr a) malloc = doMalloc Dummy where doMalloc :: Storable b => Dummy b -> IO (Ptr b) doMalloc dummy = mallocBytes (sizeOf dummy) In any case, for me this is not a compelling reason to break several widely used interfaces. Roman