Re: Access type to member procedure of instance (Object Oriented programming in Ada)

[Adam Beneschan <adam@irvine.com>]

On Monday, November 19, 2012 4:05:16 PM UTC-8, Randy Brukardt wrote:
> "Randy Brukardt" wrote in message 

> I should point out that I don't think that the code you wrote actually would 
> solve the problem you were trying to solve. That's because you usually need 
> to make dispatching calls, and such a call would be bound to a subprogram 
> when you wrote the name "Message.Print" and not when you actually made the 
> call.

If Message had type Message_Type'Class, I'd assume that at some point, Message.Print'Access would need to determine which Print subprogram would be called, and figure out the address of it.  I don't think it matters whether it's done when the 'Access value is computed or when the call is made, since the tag of an object can't be changed during the object's lifetime.  I could be wrong, though; maybe I've missed a case where it matters.  (But I'm not concerned about the possibility of an object's tag being changed through extralegal means like Unchecked_Conversion.)

                           -- Adam