Re: Ada 95 dispatching question

[hainque@news.enst.fr (Olivier Hainque)]

Adam Beneschan (adam@irvine.com) wrote:
: What should the following program output?  I'm trying to get it to
: output

:     3/TRUE/"abcdefghij"/ 15

: but it outputs instead

:     3/TRUE/???

The output is correct, ...

: If the output is correct, then why?  In particular, is the line marked
: "<=== HERE" a dispatching call, and if not, why not?  And how would I
: have to modify the program to get it to do what I'd like it to do,
: given that declaring do_to_aux and do_to_rec in PACK1 is not an
: option?

The call

:         do_to_aux (auxinfotype2 (r.f3.all));       -- <=== HERE

is not a dispatching call since the actual argument you give is
not classwide typed. 

In fact, you actually tell : "I want to call the do_to_aux procedure
with an argument of type 'auxinfotype2'".

For this call to be dispatching, you have to provide a classwide
argument. I think the following will do :

:         do_to_aux (auxinfotype2'Class (r.f3.all)); 


Hope this helps.

-- Olivier Hainque

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