Opaque Type: wat is het, some en any in Swift

func makeInt() -> some Equatable {
    return 42
}

func makeString() -> some Equatable {
    return "Hello"
}

// Compiler weet dat makeInt Int retourneert
// makeInt() == makeString() — ❌ fout, verschillende typen

// Generic: caller kiest type
func identity<T>(_ value: T) -> T { value }
let x: Int = identity(42)

// Opaque: functie verbergt type
func makeSomeEquatable() -> some Equatable { 42 }
let y = makeSomeEquatable()

func areEqual(_ a: some Equatable, _ b: some Equatable) -> Bool {
    // a en b — potentieel verschillende typen, == werkt niet direct
    return isEqual(a, b)
}

func isEqual<T: Equatable>(_ a: T, _ b: T) -> Bool {
    return a == b
}

protocol Drawable {
    func draw()
}

// some: statisch type is bekend
func makeDrawable() -> some Drawable {
    return Circle() // Enkel retourtype
}

// any: dynamisch, kan verschillende typen opslaan
var shapes: [any Drawable] = [Circle(), Square()]
shapes.append(Triangle())

func makeReversedCollection<T>(
    of array: [T]
) -> some Collection {
    return array.reversed()
}

let result = makeReversedCollection(of: [1, 2, 3])
// result — ReversedCollection>, hidden from caller
for item in result {
    print(item)
}

struct ContentView: View {
    var body: some View {
        VStack {
            Text("Hallo")
                .font(.title)
            Button("Raak me aan") {
                print("Aangeraakt")
            }
        }
        .padding()
    }
}