From: dd@sei.cmu.edu (Dennis Doubleday)
Subject: Re: Ada language revision
Date: 23 Nov 88 13:37:52 GMT [thread overview]
Message-ID: <7796@aw.sei.cmu.edu> (raw)
In-Reply-To: leake@cme-durer.ARPA's message of 22 Nov 88 14:37:13 GMT
In article <739@marvin.cme-durer.ARPA> leake@cme-durer.ARPA (Stephe Leake) writes:
>In article <7882@nsc.nsc.com> rfg@nsc.nsc.com (Ron Guilmette) writes
>> I have some problems with limited private types too. Specifically, if such
>> types are really only accessable through a "limited" functional interface,
>> then why shouldn't we be able to declare such types in the public part of
>> a package and then defer the full declaration until the package body?
>
>What would this gain? Do you have any specific examples where this
>would have improved the readability or functionality of an
>application? Let's not just suggest changes because they "sound good".
>Let's put some thought into it, including concrete examples.
There is a VERY good reason for it, if you're at all concerned about
portability. The declaration of a limited private type is an
IMPLEMENTATION decision. It doesn't belong in the specification, it
belongs in the body. If I'm trying to export some abstract data type
from a package, I'd like to have a specification that could be moved,
intact, from one machine to another. Only the body should need
changing. However, since I must give the full declaration of the type
in the private part of the spec instead of in the body, it may be that
I will have to change that part of the spec if I want to port the
package to a machine which requires a different implementation of the
type.
Why does your post sound so hostile? How do you know that Ron hasn't
put any thought into his suggested changes?
Dennis Doubleday dd@sei.cmu.edu
Software Engineering Institute (412)268-5873
Carnegie Mellon University
Pittsburgh, PA 15213
next prev parent reply other threads:[~1988-11-23 13:37 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
1988-11-14 13:20 Ada language revision Stanley Roger Allen, AdaDude
1988-11-15 23:28 ` Wilmer Rivers
1988-11-16 19:06 ` William Thomas Wolfe,2847,
1988-11-17 15:34 ` Stephe Leake
1988-11-18 16:39 ` Steve Tynor
1988-11-18 19:22 ` Ron Guilmette
1988-11-23 22:22 ` William Thomas Wolfe,2847,
1988-11-29 15:35 ` Stephe Leake
1988-11-18 0:32 ` Ron Guilmette
1988-11-22 14:37 ` Stephe Leake
1988-11-23 13:37 ` Dennis Doubleday [this message]
1988-11-23 19:41 ` Steve Tynor
1988-11-23 21:14 ` Richard Pattis
1988-11-25 20:36 ` Robert Firth
1988-11-29 15:12 ` limited private types Stephe Leake
1988-12-01 23:06 ` Ron Guilmette
1988-12-05 1:48 ` Paul Stachour
1988-12-05 12:31 ` Reference Semantics William Thomas Wolfe,2847,
1988-12-06 0:29 ` Paul Stachour
1988-12-07 1:07 ` Reference Semantics, assignment overloading, etc Ray Trent
1988-12-08 17:36 ` Reference Semantics, assignment ryer
1988-12-06 16:56 ` limited private types ryer
1988-12-06 20:09 ` stt
1988-12-07 15:51 ` Stephe Leake
1988-11-21 15:40 ` Ada language revision stt
-- strict thread matches above, loose matches on Subject: below --
1988-11-28 22:19 Collective response to := messages Geoff Mendal
1988-11-29 14:39 ` Dennis Doubleday
1988-11-29 21:08 ` Ray Trent
1988-11-30 14:37 ` Stephe Leake
1988-12-01 14:54 ` David S. Rosenblum
1988-12-02 20:21 ` William Thomas Wolfe,2847,
1988-12-04 21:15 ` David S. Rosenblum
1988-12-04 23:27 ` William Thomas Wolfe,2847,
1988-12-05 14:46 ` David S. Rosenblum
1988-12-05 21:23 ` William Thomas Wolfe,2847,
1988-12-07 17:33 ` Stephe Leake
1988-12-07 16:03 ` Definition of pass by reference Robert Eachus
1988-12-07 17:15 ` Collective response to := messages Stephe Leake
1988-12-07 16:07 ` Stephe Leake
1988-12-09 3:15 ` David S. Rosenblum
1988-12-01 21:31 ` Ray Trent
1988-12-07 16:21 ` Stephe Leake
1988-11-30 16:29 ` David S. Rosenblum
1988-11-30 18:29 ` William Thomas Wolfe,2847,
1988-11-30 22:28 ` David S. Rosenblum
1988-12-01 3:09 ` William Thomas Wolfe,2847,
1988-12-01 15:16 ` David S. Rosenblum
1988-12-02 19:31 ` William Thomas Wolfe,2847,
1988-12-04 21:03 ` David S. Rosenblum
1988-12-05 2:34 ` William Thomas Wolfe,2847,
1988-12-05 14:07 ` David S. Rosenblum
1988-12-07 17:26 ` Stephe Leake
1988-12-06 19:16 ` Collective response to := messa stt
1988-12-09 3:39 ` David S. Rosenblum
1988-11-30 19:13 ` CORRECTION Re: Collective response to := messages David S. Rosenblum
1988-12-01 18:31 ` Ray Trent
1988-12-02 14:49 ` David S. Rosenblum
1988-12-05 17:33 ` Collective response to := messa stt
1988-11-30 18:24 ` Collective response to := messages Robert Eachus
1988-12-02 14:58 ` David S. Rosenblum
1988-12-02 19:34 ` Mark C. Adolph
1988-12-05 17:15 ` Collective response to := messa stt
1988-11-29 21:44 ` Collective response to := messages William Thomas Wolfe,2847,
1989-07-26 20:34 Memory Access Question tony
1989-07-27 13:06 ` richard a hammond
1989-07-27 18:53 ` Ray Trent
1989-07-28 0:48 ` Mike Murphy
1989-08-02 13:23 ` Mike Walsh
1989-08-02 20:20 ` Mike Murphy
1989-07-29 0:00 ` Brian Sullivan
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox