On 2001-07-24T16:51:54-0700, [EMAIL PROTECTED] wrote:
> Hello,
>
> Is it possible in Haskell to access the underlying machine bit
> representation of a Float or Double value?
>
> I need to be able to be able to send this bit representation as a
> list of bytes in network byte order to a process running on a
> different platform (with a different host byte order to my
> platform).
>
> For reference, I run Haskell under Linux on Intel. The processes I
> want to communicate with run under Sun Solaris, Hitachi HPUX and
> Java everywhere.
>
> Any suggestions, for any Haskell translator much appreciated.
If you're using GHC, you should be able to get at the raw bits of the
machine representation using some Storable + Ptr + MarshallAlloc
trickery. (These are modules in -package lang.)
I tested the following on GHC5 on i386-linux:
module Cast (cast) where
import Storable (Storable, sizeOf, peek)
import MarshalUtils (withObject)
import IOExts (unsafePerformIO)
import Ptr (castPtr)
cast :: (Storable a, Storable b) => a -> b
cast a = b where
b | sizeOf a == sizeOf b =
unsafePerformIO $ withObject a $ peek . castPtr
I was able to get
(cast :: Int -> Char) 98 == 'b'
This might work with other compilers as well, but I don't know...
Fun fun fun! More efficient implementations?
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