Sven Panne wrote:
* You use an internal class HostAddr and make two type synonyms an instance of it.
You must have downloaded the first version of the patch that I posted a few weeks ago. The updated version doesn't have this rather unpleasant wart. Unfortunately, Trac won't let me drop old versions of a patch.
* The types and values of AddrInfoFlags/NameInfoFlags are not very Haskell-like. Using
data AddrInfoFlag = Passive | CanonName | NumericHost | ...
and [AddrInfoFlag] instead of AddrInfoFlags is much nicer.
OK, I'll update the interface to look like this. It would be nice if there were helper functions in Foreign.Marshal.Utils or Data.Bits to make this a more mindless operation: import Data.Bits import Data.List (foldl') packBits :: (Eq a, Bits b) => [(a, b)] -> [a] -> b packBits mapping xs = foldl' pack 0 mapping where pack acc (k, v) | k `elem` xs = acc .|. v | otherwise = acc unpackBits :: Bits b => [(a, b)] -> b -> [a] unpackBits mapping bits = foldl' unpack [] mapping where unpack acc (k, v) | bits .&. v == 0 = acc | otherwise = k:acc It's simple boilerplate, but nice not to need to write. This would make the conversion process very tidy: aiMapping = [(AI_PASSIVE, #const AI_PASSIVE), (AI_CANONNAME, #const AI_CANONNAME), ...and so on...] packAIFlags = packBits aiMapping unpackAIFlags = unpackBits aiMapping Assuming people like the interface, should I submit this as a separate proposal, or just fold it into Network.Socket?
Alas, the X11 package is not nice regarding the last item, either... :-(
True. But there's an SoC proposal to add XCB bindings, which could
presumably use this bit-swizzling code :-)