Re: Visibility of Indexing aspects

["Dan'l Miller" <optikos@verizon.net>]

On Friday, July 20, 2018 at 11:11:13 AM UTC-5, AdaMagica wrote:
> Am Freitag, 20. Juli 2018 14:08:11 UTC+2 schrieb Jere:
> > I was under the impression that scope and visibility were two different
> > things.  If I understand you correctly, it sounds like you are saying
> > that
> > 
> > package Things is
> >    --One scope
> > private
> >    --another scope
> > end Things;
> > 
> > I was under the impression that it was more like:
> > 
> > package Things is
> >    --One scope
> > private
> >    --same scope but different visibility
> > end Things;
> 
> The scope of every declaration start with the place of the declaration, so in a package or any declarative region, there are many scopes, some of which are visible, others not.
> 
> > Also how does this reconcile with:
> > 
> > 8.3 (23.1/3):
> > An attribute_definition_clause or an aspect_specification is
> > visible everywhere within its scope.
> > 
> > That section makes it sound like aspects created in the private
> > section are indeed visible in the public section.
> 
> Why do you think so?  
> 
> > Couple that with the section you mentioned:
> > 
> > 8.2(10.1/3) The scope of an aspect_specification is identical to 
> > the scope of the associated declaration.
> 
> "associated" means the declaration (syntax) in which it appears. This is here in the private part in the full declaration, so it's *not* visible in the public part.
> 
> BTW: You should definitely report this severe bug to AdaCore.

ARG members, this is why formalizing all the definitions is so important.  (In full support of Jere's point), one would expect “associated” to be transitive.  One would expect the lack of transitivity only with an overtly-defined new narrower term, such as ‘directly associated’, in that:  immediate scope is directly associated with the declarative statement within the private section of the package (and then the visibility would be tied to this immediate scope and thus to this •direct• association.  If Jere's interpretation is to be prohibited, then it must be prohibited via tightening the sloppy definitions, most especially the lack of definitions.

And if any reader thinks that this line of reasoning is incorrect, I offer the rather strong counter-example of AdaCore's current implementation of GNAT as likewise apparently interpreting the _LRM_ according to Jere's interpretation of “associated”, not according to AdaMagica's interpretation of public declarations in partial view ••not being associated•• with private declarations in the full view.