Elevated `foldr1`

elevatedFoldr1.hs

import Data.Foldable (foldr1)

{-
  Fold a list of values into an elevated operator.
  This allows applying an operator on a list which values type do not
  support the operator, but can be casted to a type which does.
  
  The `toLifted` function casts every value of `values` to a type that `op`
  accepts, then `fromLifted` casts back the result to the `values` type.

  Elevated |                -- op --
           |              /          \
           |      ↑ toLifted ↑    ↓ fromLifted ↓
           |           /                \
  Normal   | values --                    -- (result)
-}
elevatedFoldr1 :: (a -> a -> a) -> (b -> a) -> (a -> b) -> [b] -> b
elevatedFoldr1 op toLifted fromLifted values =
    fromLifted $ foldr1 op (map toLifted values)

lift -> toLifted and demote -> fromLifted
elevatedCall -> elevatedFoldr

Thanks for the suggestions @jake-87