Can I make a variable public and readonly (outside where was declared) at same time?

[bearophile via Digitalmars-d-learn]

Marc Schütz:

> Alternatively, you could create a union with a private and a 
> public member with the same types, but I wouldn't recommend it. 
> Besides, the members would need to have different names:
>
>     class Foo {
>         union {
>             private int a;
>             public int b;
>         }
>     }

You can call them a and a_. Why are you not recommending this 
solution? It looks cool (if it works).

Bye,
bearophile