comp.lang.ada
 help / color / mirror / Atom feed
From: woodruff@calaveras.llnl.gov (John Woodruff B481)
Subject: Package names & visibility
Date: 1996/07/03
Date: 1996-07-03T00:00:00+00:00	[thread overview]
Message-ID: <udspb9atdo.fsf@calaveras.llnl.gov> (raw)


I find myself puzzled by some consequence of a visibility rule in naming
packages, and I wonder if I need to reconsider my plan for making up
these names (of if there is a simple re-phrasing that I should know).

In very simple form, I have a package specification that declares some
type (and other declarations as well of course).

Let's say my system will have motors, sensors, switches, etc.  So I will
operate my motors with a package such as

package Motor is
   type  Yes_It_Is  is new Integer ;
end Motor ;

But I need other information in addition to the direct control that I'll
implement in the package Motor.  Therefore I thought I'd make a family
of packages to hold info about motors and sensors etc

package Info_About is
  -- a package that will have children
end Info_about ;

My intention is to have children packages carry different sorts of
info_about;  So there will be a package

with Motor ;
package Info_About.Motor is
  A  : Motor.Yes_It_Is ;
  --  (I'm not *really* going to declare a visible object!)
end ;

My thinking was that Info_about.Motor will hold some data values (which
are of types defined by the Motor package).

But I can't seem to refer to the type Yes_It_Is!  My friend Gnat tells me
info_about-motor.ads:3:13: "Yes_It_Is" not declared in "Motor"

This message clearly states that the visibility of info_about.motor is
hiding the package Motor where the type is declared.

Please suggest a way that I can refer to the identifiers that are
declared in Motor from inside the package Info_about.motor.   Thx!

--
John Woodruff	                                          N I F   \ ^ /
Lawrence Livermore National Lab                         =====---- < 0 >
510 422 4661                                                      / v \




             reply	other threads:[~1996-07-03  0:00 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1996-07-03  0:00 John Woodruff B481 [this message]
1996-07-05  0:00 ` Package names & visibility Jon S Anthony
1996-07-06  0:00   ` Robert A Duff
1996-07-08  0:00   ` Jon S Anthony
replies disabled

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox