Primes ( Haskell ) (酷いｗ)

primes.hs

-- author: Leonardne @ NEETSDKASU

import qualified Data.IntSet as IS

hoge p = [p,p+p..]

fuga p = unzip . map (break (> p))

piyo (s, e, xs) =
    case IS.minView s of
    Nothing     -> piyo $ foo e xs
    Just (p, t) -> p : piyo (bar p t e xs)
        
foo e xs = (t, r, ys)
    where
        r = e+100000
        s = IS.fromList [e+2,e+4..r]
        (d, ys) = fuga r xs
        t = foldl (foldl (flip IS.delete)) s d

bar p s e xs = (t, e, ys)
    where
        (d, ps) = break (> e) $ hoge p
        t = foldl (flip IS.delete) s d 
        ys = ps:xs

baz = 2 : 3 : piyo (IS.empty, 3, [hoge 3])


main = print $ take 100 $ drop 19950 $ baz

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https://ideone.com/cIK9Xv