[Haskell-cafe] convert a list of booleans into Word*

Jochem Berndsen jochem at functor.nl
Wed Sep 30 09:44:40 EDT 2009


Bulat Ziganshin wrote:
> Hello Paul,
>
> Wednesday, September 30, 2009, 1:18:03 PM, you wrote:
>
>> 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.
>
> sum . zipWith (*) (map (2^) [0..])

I'd turn this into
> sum . zipWith (*) (iterate (2*) 1)
, but it's probably not very important.

Regards, Jochem
-- 
Jochem Berndsen | jochem at functor.nl | jochem@牛在田里.com


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