From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID
	autolearn=no autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,68448d6fdcce63ae
X-Google-Attributes: gid103376,public
From: Stephen Leake <Stephen.Leake@gsfc.nasa.gov>
Subject: Re: Protected Objects: Scoping problem.
Date: 1998/06/17
Message-ID: <uemwnzzlr.fsf@gsfc.nasa.gov>#1/1
X-Deja-AN: 363588400
References: <6m3kj4$ev0@nntp02.primenet.com>
Organization: NASA Goddard Space Flight Center -- Greenbelt, Maryland USA
Newsgroups: comp.lang.ada
Date: 1998-06-17T00:00:00+00:00
List-Id: <comp.lang.ada>


Robert Worne <rworne@primenet.com> writes:

> I am having a problem with scoping on protected objects.
> 
> I am working on a package that has a protected object that
> communicates to other packages via a "read".  A "write" in that object 
> should be visible only as an internal subprogram, and not visible to the
> outside world.  A simplified version from the Ada documents on-line is:
> 
> package Protected_Variable is
> 
> type T is new integer;
>     
>    protected Variable is
>    function Read return T;
>    procedure Write(Value: T);  -- I do NOT want this accessible to outside
>                                -- packages!
> private
>    Data: T;
> end Variable;
> end Protected_Variable;

That's precisely what the private part of the protected type is for.
Just declare Write in the private part:

package Protected_Variable is
   
   type T is new integer;
   
   protected Variable is
      function Read return T;

   private
      procedure Write(Value: T);  -- NOT accessible to outside packages
      Data: T;
   end Variable;
end Protected_Variable;

<snip> 

-- Stephe