## Motivation Just as appending together regular lists is a common task, appending non-empty lists is also a common task. Having functions to do so in the prelude would make working with non-empty lists much easier and prevent users from re-implementing the same functions over and over. ## Proposal I propose adding an `append` function to the `Data.List.NonEmpty` library. This would include, at minimum, a definition for `NonEmpty a -> NonEmpty a -> NonEmpty a`. It could also include definitions for `NonEmpty a -> [a] -> NonEmpty a` and `[a] -> NonEmpty a -> NonEmpty a`. Here are sample implementations for each case. They currently have very verbose names because I couldn't think of anything better off the top of my head. I assume the first would simply be named `append`, but I don't have great ideas for the second and third. ```haskell appendNonEmptyNonEmpty :: NonEmpty a -> NonEmpty a -> NonEmpty a appendNonEmptyNonEmpty (x1 :| xs) ys = x1 :| xs ++ toList ys appendNonEmptyRegular :: NonEmpty a -> [a] -> NonEmpty a appendNonEmptyRegular (x :| xs) ys = x :| xs ++ ys appendRegularNonEmpty :: [a] -> NonEmpty a -> NonEmpty a appendRegularNonEmpty [] ys = ys appendRegularNonEmpty (x:xs) ys = x :| xs ++ toList ys ```