If you have a value of type Int -> Char -> Bool -> Float, you can use multiuncurry @(->) to convert it to a value of type NP Identity '[Int,Char,Bool] -> Float, where NP is a n-ary product from sop-core. multicurry @(->) goes in the other direction.

If you have a value of type Either Int (Either Char (Either Bool Float), you can use multiuncurry @Either to convert it to a value of type Either (NS Identity '[Int,Char,Bool]) Float, where NS is a n-ary sum from sop-core. multicurry @Either goes in the other direction.