Namespace and Implicit member chains

Namespace.swift

// 1. Create a generic namespace we can ue to 'hang' values off
public struct Namespace<Base> { }

// 2. Add a namespace to a type(s) with the desired name
extension Color {
    public static var theme: Namespace<Self> { .init() }
}
extension Font {
    public static var theme: Namespace<Self> { .init() }
}

// 3. Add values to the namespaces
extension Namespace where Base == Color {
    public var primary: Color { .blue }
}
extension Namespace where Base == Font {
    public var headline: Font { .custom("MyFont", size: 30, relativeTo: .headline) }
}

// 4. Profit! (Enjoy the benefits of both namespaces and autocomplete)
Text("Foo")
    .foregroundColor(.theme.primary)
    .font(.theme.headline)