Simple named arguments, without reordering.

named-args.hs

{-# language OverloadedLabels #-} -- other extensions omitted
import Data.Kind
import GHC.OverloadedLabels
import GHC.TypeLits

infix 1 ::#
data NamedType = Symbol ::# Type

data Tag (t :: NamedType) where Tag :: Tag t
instance IsLabel s (Tag t) where
    fromLabel = Tag

infixr 0 -#>
type family (-#>) a b where
    (-#>) (s ::# ty) b = Tag (s ::# ty) -> ty -> b
    

-- | example function
cylinderVol :: "height" ::# Double -#> "radius" ::# Double -#> Double
cylinderVol _ h _ r = h * pi * r * r

main = print $ cylinderVol #height 5 #radius 2