Re: Need advice re package organization.

["Warren W. Gay VE3WWG" <ve3wwg@cogeco.ca>]

Robert I. Eachus" <rieachus@attbi.com> wrote in message news:3F22F9E9.3040307@attbi.com...
> Warren W. Gay VE3WWG wrote:
>
> > [As a side note, I sometimes wonder if an enhancement to the Ada0Y
> > language might be to be able to specify a limited visibility of a
> > parent package's object's internals (a la not "protected" type in
> > C++). A protected class in C++ allows derived code to mess with the
> > internals, whereas normally the parent object's elements are a
> > black box. Use of limited visibility helps to reduce code coupling.]
>
> Actually, that is what a private child package is for.  It allows you to
> move all of the "useful" internals out of a package body to a place
> where the body and all the child packages can access them.

Actually, what I had in mind was the object visibility here (not
package visibility). When deriving from existing tagged records, there
is no way to limit the visibility of the parent object's members (a
la "protected" in C++/Java). A derived object can freely mess with any
tagged record's members, as it sees fit. Information hiding
and reduced coupling practices suggests that this is not the safest
route (best to use the existing parent object methods to mess with
the "parent members").

-- 
Warren W. Gay VE3WWG
http://home.cogeco.ca/~ve3wwg