Helix code lens and code actions for Haskell

helix.hs

-- Follow instructions from (https://www.haskell.org/ghcup/) to install Haskell-Language-Server 

-- Neither do code actions nor code lenses are available when selecting eligible code, while in other 
-- editors they are available

-- More code actions are available in other editors
-- func xs = sum xs
-- func = sum
func :: (Foldable t, Num a)=> t a -> a
func xs = foldl (+) 0 xs

-- The type signature can be added in other editors through code lens
-- f :: Num a => a -> a -> a
f x y = x * y + 2