Re: Converting things to and from binary

20 May 2003


      On 20 May 2003 09:07:24 +0200
ketil@ii.uib.no (Ketil Z. Malde) wrote:
...
Glynn Clements  writes:
...
George Russell wrote:
...
...
The general problem to solve is "How to we convert things to and
from a binary format, so they can be efficiently written to and
from disk".  I have solved this (incompletely) twice myself,
...
Possibly the best way to handle this would be to extend the Storable
class, e.g.
...
class Storable a where
          :
[snip]    :
  toByteArray :: a -> Array Int Word8
  fromByteArray :: Array Int Word8 -> a
I wonder if this could be used to address a question (or perhaps
"frustration" is a better term), namely that of efficient packing of
data structures in memory.
Would it be possible to separate binary I/O in two layers, the binary
layer converting to/from (U?)Arrays of Word8, and another, the I/O
layer, reading and writing such arrays?
Something almost entirely, but not quite, unlike:
class Binary a where
                toBin :: a -> Array Int Word8
                toBinList :: [a] -> Array Int Word8
                fromBin :: Array Int Word8 -> a  -- perhaps with
                offset? fromBinList :: Array Int Word8 -> [a]
hPutArray :: Handle -> Array Int Word8 -> IO ()
        hGetArray :: ...
        writeBinaryFile :: FilePath -> Array Int Word8 -> IO ()
        :
-kzm
What's wrong with NHC's Binary/BinArray library?  There seems to be a
GHC port on the GreenCard page.

Re: Converting things to and from binary

Derek Elkins