testsuite/tests/mdo/should_run/mdorun004.hs


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{-# LANGUAGE RecursiveDo #-}

-- check that mdo does perform segmentation
t :: IO [Int]
t = mdo xs <- return (1:xs)
        print (length (take 10 xs))     -- would diverge without segmentation
        return (take 10 xs)

main :: IO ()
main = t >>= print