-- | @map21 (head, last) . sublistByIndex (i, j) $ [0..] == (i, j)@
propSublistByIndex :: Int -> Int -> Property
propSublistByIndex i j = i >= 0 && j > i ==> (map21 (head, last) . sublistByIndex (i, j)) [0..] == (i, j)
propSublistByIndex :: Int -> Int -> Property
propSublistByIndex i j = i >= 0 && j > i ==> (map21 (head, last) . sublistByIndex (i, j)) [0..] == (i, j)
propSublistByIndex i j = i >= 0 && j > i ==> (map21 (head, last) . sublistByIndex (i, j)) [0..] == (i, j)