generic child package

generic child package

[nblanpain]

Is my example correct ? :

------------------------------
generic
   with type T_Toto is private;
package Parent is
   pragma Pure;
end Parent;
------------------------------

------------------------------
generic
package Parent.Child1 is
   type T_Child1 is tagged private;
   ....
end Parent.Child1;
------------------------------

------------------------------
generic
   with P_Child1 is new Parent.Child1;   ----- or with P_Child1 is new
Parent.Child1 (<>); ?????
package Parent.Child2 is
   type T_Child2 is new P_Child1.T_Child1 with private;
   ....
end Parent.Child2;
------------------------------

Is there or problem or is it correct ?

Thanks,

Re: generic child package

[Dmitry A. Kazakov]

On 22 Jul 2006 23:44:58 -0700, nblanpain@hotmail.com wrote:

> Is my example correct ? :
> 
> ------------------------------
> generic
>    with type T_Toto is private;

type T_Toto is private;

> package Parent is
>    pragma Pure;
> end Parent;
> ------------------------------
> 
> ------------------------------
> generic
> package Parent.Child1 is
>    type T_Child1 is tagged private;
>    ....
> end Parent.Child1;
> ------------------------------
> 
> ------------------------------
> generic
>    with P_Child1 is new Parent.Child1;   ----- or with P_Child1 is new
> Parent.Child1 (<>); ?????

with package P_Child1 is new Parent.Child1;

> package Parent.Child2 is
>    type T_Child2 is new P_Child1.T_Child1 with private;
>    ....
> end Parent.Child2;
> ------------------------------
> 
> Is there or problem or is it correct ?

What about:

generic
package Parent.Child1.Grandchild1 is
   type T_Grandchild1 is new T_Child1 with private;
   ....
end Parent.Child1.Grandchild1;

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

Re: generic child package

[nblanpain]

yes excuse me :

generic
   type T_Toto is private;

but are you sur it is :
 with P_Child1 is new Parent.Child1;
and not
with P_Child1 is new Parent.Child1 (<>);

thanks,


Dmitry A. Kazakov a écrit :

> On 22 Jul 2006 23:44:58 -0700, nblanpain@hotmail.com wrote:
>
> > Is my example correct ? :
> >
> > ------------------------------
> > generic
> >    with type T_Toto is private;
>
> type T_Toto is private;
>
> > package Parent is
> >    pragma Pure;
> > end Parent;
> > ------------------------------
> >
> > ------------------------------
> > generic
> > package Parent.Child1 is
> >    type T_Child1 is tagged private;
> >    ....
> > end Parent.Child1;
> > ------------------------------
> >
> > ------------------------------
> > generic
> >    with P_Child1 is new Parent.Child1;   ----- or with P_Child1 is new
> > Parent.Child1 (<>); ?????
>
> with package P_Child1 is new Parent.Child1;
>
> > package Parent.Child2 is
> >    type T_Child2 is new P_Child1.T_Child1 with private;
> >    ....
> > end Parent.Child2;
> > ------------------------------
> >
> > Is there or problem or is it correct ?
>
> What about:
>
> generic
> package Parent.Child1.Grandchild1 is
>    type T_Grandchild1 is new T_Child1 with private;
>    ....
> end Parent.Child1.Grandchild1;
> 
> -- 
> Regards,
> Dmitry A. Kazakov
> http://www.dmitry-kazakov.de

Re: generic child package

[Ludovic Brenta]

nblanpain@hotmail.com writes:
> yes excuse me :
>
> generic
>    type T_Toto is private;
>
> but are you sur it is :
>  with P_Child1 is new Parent.Child1;

Yes, that's correct.  Have you looked at the Wikibook chapter on
generics?  It is here:

http://en.wikibooks.org/wiki/Ada_Programming/Generics

> and not
> with P_Child1 is new Parent.Child1 (<>);

-- 
Ludovic Brenta.

Re: generic child package

[Dmitry A. Kazakov]

On 23 Jul 2006 10:57:06 -0700, nblanpain@hotmail.com wrote:

> yes excuse me :
> 
> generic
>    type T_Toto is private;
> 
> but are you sur it is :
>  with P_Child1 is new Parent.Child1;
> and not
> with P_Child1 is new Parent.Child1 (<>);

Side comment. Both are wrong. It must be "with package <formal-name> is
..".

The box (<>) indicates that the parameters of a package instance could be
any. Parent.Child1 does not have parameters of its own, so no box.

In (rare) case you wished to pass P_Child1, child of a *different* instance
of Parent, you would pass its Parent as well:

with Parent.Child1;

generic
   with package P is new Parent (<>);
       -- Parent has parameters, we don't care which, so the box
   with package P_Child1 is new P.Child1;
       -- Note, how P_Child1 refers to P, an instance of Parent potentially
       -- different from the parent of Child2
package Parent.Child2 is
   type T_Child2 is new P_Child1.T_Child1 with null record;
end Parent.Child2;

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de