// You should not write to Val when using RxRef
public static RxRef <A> toRxRef <A>(this PrefVal <A> val)
{
var rx = new RxRef <A>(val.value);
rx.subscribe(v => val.value = v);
return(rx);
}
// You should not write to Val when using RxRef
public RxRef <A> toRxRef()
{
var rx = new RxRef <A>(read);
rx.subscribe(v => write(v));
return(rx);
}