Thought it would be nice to create a custom stack implementation. Immediately ran into all kinds of walls.

gistfile1.txt

struct Stack<Item>: View where Item: View {
    let items: [Item]

    init(@ViewBuilder items: () -> Item) {
        fatalError("How to get the views out of the view builder's result (TupleView) into self.items?")
    }

    var body: some View {
        fatalError("How to layout self.items in a Group/ZStack?")
        return EmptyView()
    }
}

You could make your own @_functionBuilder equivalent of ViewBuilder where you can build a type you can peek at. Agree it's a little bogus the way it's all hidden from the outside tho!