On Fri, 18 Dec 2009, Gregory Crosswhite wrote:
Yay, advancePtr is exactly what I needed! I totally missed that one in the docs.
Also thanks to those of you who pointed me to the scoped type variables feature, since I had figured that a feature liked that had to exist but I just didn't know where to look for it.
You do not need the Scoped Type Variables feature here, although it may simplify writing. I remember we had a similar thread here, recently. A solution can be: sizeOfPtr :: Ptr a -> a -> Int sizeOfPtr _ x = sizeOf x to be called by (sizeOfPtr ptr undefined). I have added this example to: http://www.haskell.org/haskellwiki/Scoped_type_variables#Avoiding_Scoped_Typ... But in order to be found in Category:FAQ we might need a different title.