Re: Unchecked_Deallocation with tagged types

[Thomas <fantome.forums.tDeContes@free.fr.invalid>]

In article <b37bc687-b72f-4bc4-858c-77dc9b878cffn@googlegroups.com>,
 Gautier write-only address <gautier_niouzes@hotmail.com> wrote:

> > Well, P'Free can also be in another package... Of course, we are talking 
> > here only about the direct, actual deallocation. 
> > 
> > If you want to precisely know where deallocation is used, use AdaControl 
> > (for any solution). If you want to be confident that there is no direct 
> > deallocation in a module, the generic wins. 
> 
> It loses because you can have direct, immediate deallocation without the 
> "with Ada.Unchecked_Deallocation" somewhere in the context clause.
> 
> pack.ads:
> 
> with Ada.Unchecked_Deallocation;
> package Pack is
>   type IA is access Integer;
>   procedure Release is new Ada.Unchecked_Deallocation (Integer, IA);
> end;
> 
> ----
> proc.adb:
> 
> with Pack;
> procedure Proc is
>   use Pack;
>   P : IA;
> begin
>   P := new Integer;
>   Release (P);
> end;


what J-P. Rosen meant was that P'Free could be in the body of 
Pack.Release, and then it would not be in Proc either.


perso i like the design with the "generic".
(I'm used to it anyway, although of course it's worse than not needing 
explicit Deallocation.)

but the question is: why in the specification ???


actually i need to know more about your case:

- do you find it ok to put the access types in the package 
specification, and then not have control over what they become?

- or don't you want that, but you regularly become in situations where 
you have no choice (for example because you need components of which you 
are not the author)?


what's your opinion about String_Access and Free in 
Ada.Strings.Unbounded?

I don't understand what they are doing here, since this package is made 
to avoid needing them...

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