enum Shape{ case Square, Triangle }

enum Color{ case Red, Green }

func apply(_ filters: [Filter]){
   for filter in filters{
      if it's a Shape filter, apply that
      if it's a Color filter, apply that
   }
}

let filters = [Shape.Triangle, Color.Green, Color.Red] // get objects which are triangle, or have color red, or have color green

enum Filter{
    enum Shape{...}
    enum Color{...}
}

let filters: [Filter] = [Filter.Shape.Square, Filter.Color.Green, Filter.Color.Red]