At 2001-08-09 03:01, Simon Marlow wrote:

Ok, I agree so far. Are you suggesting the IO library should be changed?

Yes.

How?

Hmm... well the file part to use Word8s and not be stream-based. Perhaps something like this: -- data OpenFile = ... openFileReadOnly :: FilePath -> IO OpenFile openFileReadWrite :: FilePath -> IO OpenFile closeFile :: OpenFile -> IO () fileWritable :: OpenFile -> IO Bool fileLength :: OpenFile -> IO Integer setFileLength :: OpenFile -> Integer -> IO () -- fill with zeros if extending readFileBlock :: OpenFile -> Integer -> Integer -> IO [Word8] -- "readFileBlock file start length", return truncated array if past file end writeFileBlock :: OpenFile -> Integer -> [Word8] -> IO () -- would extend file if writing past end -- This covers ReadMode and ReadWriteMode. I don't really understand WriteMode, but depending on what operations that implies, that could be included too. AppendMode is by nature a weird sink-based thing and would have a separate interface: -- data AppendableFile = ... openFileAppendable :: FilePath -> IO AppendableFile closeFileAppendable :: AppendableFile -> IO () appendToFile :: AppendableFile -> [Word8] -> IO (); -- Of course, on some implementations the AppendableFile functions could be implemented with the OpenFile functions. In any case, network functions would not use the same datatypes at all. If you want to provide functions that work with different things that follow a single pattern, use classes. -- Ashley Yakeley, Seattle WA