Tue, 18 Jan 2000 18:45:52 +0300 (MSK), S.D.Mechveliani <[EMAIL PROTECTED]> pisze:
> But "filter-filter" implementation needs a constant space for
>
> head $ fst $ partition (==1) [0..n].
>
> And some recent implementations take heap+stack proportional to n.
partition _ [] = ([], [])
partition p (x:xs) = if p x then (x:ys, zs) else (ys, x:zs)
where (ys, zs) = partition p xs
runs your example in constant space.
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