Re: Inheritance with Ada types

["Hibou57 (Yannick Duchêne)" <yannick_duchene@yahoo.fr>]

On 9 fév, 03:16, Bryan <brobinson....@gmail.com> wrote:
> I created two simple
> packges as follows:
>
> parent.ads:
>
> with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;
> package Parent is
>   type Parent is abstract tagged private;
> private
>   type Parent is abstract tagged
>     record
>       Name: Unbounded_String;
>     end record;
> end Parent;
>
> derived.ads:
>
> with Parent; use Parent;
> package Derived is
>   type Derived is new Parent with private;
> private
>   type Derived is new Parent with
>     record
>       Sub_Name: Unbounded_String;
>     end record;
> end Derived;
Oops : package and type name share the same name and you there are use
clause... the use clause is particularly evil here.

> $ gnatmake -c parent derived.ads
> gcc -c derived.ads
> derived.ads:3:23: subtype mark required in this context
> derived.ads:3:23: found "Parent" declared at parent.ads:2
The message refer to
> package Parent is

> derived.ads:5:23: subtype mark required in this context
> derived.ads:5:23: found "Parent" declared at parent.ads:2
The same as above

Either rename your packages (like Parents and Deriveds ... although
the latter is not correct English) or drop the use clause and refer to
your Parent ancestor as Parent.Parent instead.

By the way, the With clause for Ada.Strings.Unbounded is missing in
Derived.ads