Maybe. I can't think of a clean way to do it. The ...

# tornadofx

[Ruckus]

Maybe. I can't think of a clean way to do it. The problem is class PropertyDelegate<T>(val fxProperty: Property<T>) : ReadWriteProperty<Any, T>.
We have no way of intercepting the incoming property and checking if it's a primitive property before the interface is implemented, so it has to be a ReadOnlyProperty<Any, Number!> and Number! has to be invariant as it's a mutable property.