Re: Visibility problems in Parent.Child configuration

[t_wolf@angelfire.com (Thomas Wolf)]

keld.nielsen@agip.it (Keld Lund Nielsen) wrote in message news:<383f908a.0207300341.1047c075@posting.google.com>...
> Dear All,
> 
> a question regarding type visibility. The configuration is as follows:
> 
> ----file Parent.ads:
>  with Ada.Numerics.Generic_Elementary_Functions;
> package Parent is
> 
>    package Float_64 is
>       type Instance is digits 15;
>         for Instance'Size use 64;
>         package Operations is
>           new Ada.Numerics.Generic_Elementary_Functions( Instance );
>    end Float_64;
> 
> end Parent;
> 
> ----file Parent.Generic_Child.ads:
>  generic
>   type Instance is private;
> 
> package Parent.Generic_Child is
>    --void...
> end Parent.Generic_Child;
> 
> 
> Then I create a test system with the structure:
> 
>   Test.Parent.Child
> 
> but when I try to create an instance of Generic_Child or just declare
> a subtype of the Parent.Float_64.Instance, then the compiler protests
> and gives the message that Float_64 is not in Parent!
> 
> Moreover, when instantiated from a simple package - say "my_package" -
> then it works perfectly, yet not from the "Test.Parent.Child".

That's because if you do e.g.

package Test.Parent.Child is

  subtype My_Float is Parent.Float_64.Instance;

end Test.Parent.Child;

the name "Parent" refers to package "Test.Parent", not
to package "Parent". To refer from within "Test.Parent" or
one of its children to the top-level package "Parent", use
"Standard.Parent". E.g.

package Test.Parent.Child is

  subtype My_Float is Standard.Parent.Float_64.Instance;

end Test.Parent.Child;

should work.

--
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Thomas Wolf                         e-mail: t_wolf@angelfire.com