Here's another approach for Bool lists with msb leftmost:
bitsToInt :: [Bool] -> Integer
bitsToInt = foldr((.(flip shiftL 1)).(+)) 0. map (fromIntegral.fromEnum)
Hallo Paul.Brauner@loria.fr, je schreef op 30-09-09 11:18:
Hello,
I haven't found a function in hackage or in the standard library that
takes a list of booleans (or a list of 0s and 1s, or a tuple of booleans
or 0s and 1s) and outputs a Word8 or Word32.
I have written one which seems very inefficient :
toWord8 :: [Bool] -> Word8
toWord8 bs = go 0 0 bs
where go n r [] = r
go n r (b:bs) = go (n+1) (if b then setBit r n else clearBit r n) bs
Is there a better way to do this out there ?
(If it helps, i'm writting a toy compression algorithm, which outputs
binary as lists of booleans, and I'd like to output that in a file).
Cheers
Paul
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