Re: Declaration of private type Containers

[Jean-Pierre Rosen <rosen@adalog.fr>]

alexander.kleppe@web.de a �crit :
> Hi all,
> 
> I'm relatively new to Ada. I have a problem, which seems pretty basic
> to me. Thus, I guess you guys have a easy solution ready.
> The only thing I want to do is to  declare a list package, whose
> Element_Type is of a private record type:
> 
> package A is
> 
> type My_Type is private
> 
> package My_Type_Lists is new Ada.Containers.Doubly_Linked_List
>      (Element_Type	=> My_Type);
> 
> private
> 
> type My_Type is
> record
> ...
> end record;
> 
> end A;
> 
> 
> GNAT compiler says, this is a "premature use of private type", which I
> accept. 
Glad to hear that you accept it. The ARG tried hard to allow something 
like this, and eventually gave up under the pressure of an exponentially 
growing mountain of cans of worms...

If My_Type_Lists is not used within My_Type itself, the easiest way is 
to instantiate it as a child package:
package A.My_Type_Lists is new Ada.Containers.Doubly_Linked_List
       (Element_Type	=> My_Type);

-- 
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            J-P. Rosen (rosen@adalog.fr)
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