+ package:numeric-prelude

add and subtract elements
Construct a complex number from real and imaginary part.
Construct a quaternion from real and imaginary part.
Append two lists, i.e.,
[x1, ..., xm] ++ [y1, ..., yn] == [x1, ..., xm, y1, ..., yn]
[x1, ..., xm] ++ [y1, ...] == [x1, ..., xm, y1, ...]
If the first list is not finite, the result is the first list.
addPair :: (Additive.C a, Additive.C b) => (a,b) -> (a,b) -> (a,b)
addPair = Elem.run2 $ Elem.with (,) <*>.+  fst <*>.+  snd
add and subtract elements