How to return different Views from switch case

I have this function in my SwiftUI code

func getShape(shape:Int, i: Int) -> some View {
    switch self.selectedShape {
    case 0:
        return Rectangle()
               .stroke(Color.pink)
               .frame(width: 150, height: 150)
               .position(CGPoint(x: scrCenterX, y: scrCenterY))
               .rotationEffect(Angle(degrees: Double(i) * Double(self.angleStep)))
    case 1:
        return Circle()
               .stroke(Color.pink)
               .frame(width: 150, height: 150)
               .position(CGPoint(x: scrCenterX, y: scrCenterY))
            .rotationEffect(Angle(degrees: Double(i) * Double(self.angleStep)))
    case 2:
        return Capsule()
               .stroke(Color.pink)
               .frame(width: 150, height: 150)
               .position(CGPoint(x: scrCenterX, y: scrCenterY))
            .rotationEffect(Angle(degrees: Double(i) * Double(self.angleStep)))
    default:
        return Rectangle()
        .stroke(Color.pink)
        .frame(width: 150, height: 150)
        .position(CGPoint(x: scrCenterX, y: scrCenterY))
            .rotationEffect(Angle(degrees: Double(i) * Double(self.angleStep)))
    }
}

and compliler says that "Function declares an opaque return type, but the return statements in its body do not have matching underlying types". If I change in all "cases" shape to e.g. Circle then code is compiled without any error. How I cold achieve returning shape based on selectedShape value? Thanks.

Solution

some View is an Opaque (to the caller) return type that is some type that conforms to View. But it has to be a specific type known at compile-time to the callee.

So, at compile-time, you need to decide which concrete type conforming to View it's going to be. It cannot be either Rectangle or Circle; it always needs to be the same type. So what you're trying to do is not possible (by design) with opaque types.

Instead, you would need to type erase into AnyView:

func getShape(shape:Int, i: Int) -> AnyView {

   switch self.selectedShape {
   case 0: return AnyView(Rectangle()
                          .stroke(Color.pink)
                          .frame (...)
                          )
   case 1: return AnyView(Circle()
                          .stroke(Color.pink)
                          .frame (...)
                          )
   // etc...
}