[Haskell-cafe] Writing binary files?

[Ron de Bruijn]

--- Sven Panne <Sven.Panne at aedion.de> wrote:

> Hal Daume III wrote:
> > There's a Binary module that comes with GHC that
> you can get somewhere (I 
> > believe Simon M wrote it).  I have hacked it up a
> bit and added support 
> > for bit-based writing, to bring it more in line
> with the NHC module.  
> > Mine, with various information, etc., is available
> at:
> > 
> >   http://www.isi.edu/~hdaume/haskell/NewBinary/
> 
> Hmmm, I'm not sure if that is what Ron asked for.
> What I guess is needed is
> support for things like:
> 
>     "read the next 4 bytes as a low-endian unsigned
> integer"
>     "read the next 8 bytes as a big-endian IEEE 754
> double"
>     "write the Int16 as a low-endian signed integer"
>     "write the (StorableArray Int Int32) as
> big-endian signed integers"
>     ...
> 
> plus perhaps some String I/O with a few encodings.
> Alas, we do *not* have
> something in our standard libs, although there were
> a few discussions about
> it. I know that one can debate ages about byte
> orders, external representation
> of arrays and floats, etc. Nevertheless, I guess
> covering only low-/big-endian
> systems, IEEE 754 floats, and arrays as a simple
> 0-based sequence of its
> elements (with an explicit length stated somehow)
> would make at least 90% of all
> users happy and would be sufficient for most "real
> world" file formats. Currently
> one is bound to hGetBuf/hPutBuf, which is not really
> a comfortable way of doing
> binary I/O.
> 
> Cheers,
>     S.
> 
Basically, I just want to have a function, that
converts a list with zeros and ones to a binary file
and the other way around. 

If I write 11111111 to a file, it would take 8 bytes.
But I want it to take 8 bits. 


		
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