prop_head2 xs = P.length xs > 0 ==> runner1 (enumPure1Chunk xs (Iter.head >> stream2list)) == tail xs
  where types = xs :: [Int]
prop_head2 xs = P.length xs > 0 ==> runner1 (enumPure1Chunk xs (Iter.head >> stream2list)) == tail xs
  where types = xs :: [Int]
prop_head2 xs = P.length xs > 0 ==> runner1 (enumPure1Chunk xs (Iter.head >> stream2list)) == tail xs
  where types = xs :: [Int]