On Mon, 2006-09-25 at 12:47 +0400, Bulat Ziganshin wrote:
Hello Robert,
jfyi: there are (very rare) computers that are not LE nor BE. afaik, VAX was one - it has smth like 1032 byte order, mixing BE in 2-byte words and LE of 2-byte words in 4-byte word (or vice versa, i'm not sure)
Yeah, I had a look for how people check such things in C and I didn't come accross any solutions for "middle-endianness" like that so I figured it was rare enough to ignore. Ultimately, it's not going to matter unless there are haskell compilers for these crazy platforms :) Is there any haskell compilers running on middle-endian platforms?
flipEndian :: Integral a => a -> a flipEndian = wordConcat . reverse . toWord8s
Heh, yeah I guess that was pretty lazy of me :)
a bit faster:
flipEndian n = let w1 = (n ) .&. 0xff w2 = (n >># 8) .&. 0xff w3 = (n >># 16) .&. 0xff w4 = (n >># 24) in (w1 <<# 24) .|. (w2 <<# 16) .|. (w3 <<# 8) .|. w4
#ifdef __GLASGOW_HASKELL__
(I# a) <<# (I# b) = (I# (a `iShiftL#` b)) (I# a) >># (I# b) = (I# (a `uncheckedIShiftRL#` b))
#else /* ! __GLASGOW_HASKELL__ */
a <<# b = a `shiftL` b a >># b = a `shiftR` b
#endif /* ! __GLASGOW_HASKELL__ */
Thanks
--
Robert Marlow