HDTenEightyP/NetNews huggingface dataset:
From: Shinji.Kono@newcastle.ac.uk (Shinji KONO)
Newsgroups: comp.lang.prolog
Subject: Re: Purpose of Prolog Semantics
Date: 10 Apr 92 15:52:07 GMT
Organization: University of Newcastle upon Tyne, UK NE1 7RU

In article <10805@cs.tulane.edu> feldman@cs.tulane.edu (Damon Feldman) writes:
>What are the advantages to the formal semantics of (pure) Prolog?

It helps programming/debug directly. When I use assert/rectract,
variable state or constraint, I understand how much I rely on formal
semantics in writing program.

>In particular what are the individual advantages of the fixpoint
>semantics and the least model semantics?

The least model semantics is suitable for testting or verifing a
program, because it does not ask how to compute it. It also allows
negation in an easy way. Is not easy to acheive the least model
semantics, but once we have it, it is easy to determine if an instance
is an element of the least model or not, since it is a set.

The fixpoint semantics requires a link between the Prolog computation 
mechanism and the success set. Computing fixpoint is rather easier.
But sometimes we cannot understand what it means.

If you have the least model semantics a priori, that's better than the
fixpoint semantics. But you haven't, the fixpoint sematnics is better. 
-- 
Shinji Kono @ Computing Laboratory, University Newcastle upon Tyne
kono@csl.sony.co.jp                     Room: 616 Claremont Bridge
from Sony Computer Science Laboratory, Inc, Japan.
From: wsbusup4@rwc.urc.tue.nl (Jan Stout)
Newsgroups: comp.lang.prolog
Subject: To J.W. Lloyd (Foundations of Logic Programming)
Date: 14 Apr 92 14:40:22 GMT
Reply-To: wsbusup4@urc.tue.nl
Organization: Eindhoven University of Technology, The Netherlands

Dear mister Lloyd,

In the 2nd Ext. edition of the book mentioned above, you claim on page 97
that _it_is_easy_to_show_that ~q is a logical consequence of comp(P) where
program P is:

   q :- ~r
   r :- p
   r :- ~p
   p :- p

We have tried to to this in our class, but with no result. We would
appreciate a little demonstration...


						Jan Stout
						wsbusup4@urc.tue.nl

P.S: Of course any comments of other newsnetters are equally welcome.
From: ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe)
Newsgroups: comp.lang.prolog
Subject: Re: debugging psychologist program.
Keywords: prolog
Date: 10 Apr 92 09:30:08 GMT
Organization: Comp Sci, RMIT, Melbourne, Australia

There is a lot more to say about this, but I'm short of time at the
moment.

In article <2476@loki.une.edu.au>, peter@loki.une.edu.au (Peter Radonyi) writes:
> % 3 response to a swearword.
> respondTo(Yourmessage) :- 
>      means([Word], profanity),      % ****
>      member([Word], Yourmessage),   % ****
>      write('Please do not use words like'), write(Word),
>      write('.'),
>      nl.

> respondTo(Yourmessage) :-
>      means(Word, Meaning),
>      member(Word, Yourmessage),
>      respond(Word, Meaning, Response),
>      printphrase(Response), nl,
>      asserta(memorised(Yourmessage)).

Do you see a difference between these?  Try

	respondTo(Yourmessage) :-
		means(Word, profanity),
		member(Word, Yourmessage),
		write('Please do not use words like '),
		write(Word), write(.), nl.

-- 
I am writing a book on debugging aimed at 1st & 2nd year CS students using
C/Modula/Pascal-like languages.  Please send suggestions (other than "you
_must_ cite "C Traps and Pitfalls") to ok@goanna.cs.rmit.oz.au
From: pereira@alice.att.com (Fernando Pereira)
Newsgroups: comp.lang.prolog
Subject: Re: To J.W. Lloyd (Foundations of Logic Programming)
Date: 14 Apr 92 21:31:11 GMT
Reply-To: pereira@alice.UUCP ()
Organization: AT&T, Bell Labs

In article <3716@tuegate.tue.nl> wsbusup4@urc.tue.nl writes:
>[...]
>that _it_is_easy_to_show_that ~q is a logical consequence of comp(P) where
>program P is:
>
>   q :- ~r
>   r :- p
>   r :- ~p
>   p :- p
>
>We have tried to to this in our class, but with no result.
Well, the completion of P is

(1)	q iff ~r.
(2)	r iff (p or ~p).
(3)	p iff p

Since p or ~p is a tautology (in classical logic), r is true by (2)
and thus q is false by (1), which means that ~q is true.

Fernando Pereira
2D-447, AT&T Bell Laboratories
600 Mountain Ave, PO Box 636
Murray Hill, NJ 07974-0636
pereira@research.att.com
Newsgroups: comp.lang.smalltalk
From: sdl@linus.mitre.org (Steven D. Litvintchouk)
Subject: Re: Query on PERT chart and/or box/line drawing/editing tools
Organization: The MITRE Corporation, Bedford, MA
	<MSMITH.92Apr8151003@volcano.ma30.bull.com>
Date: Fri, 10 Apr 1992 22:57:19 GMT


In article <MSMITH.92Apr8151003@volcano.ma30.bull.com> msmith@volcano.ma30.bull.com (Mike Smith) writes:

> I just finished looking over a tool called HotDraw.  It is archived
> at speedy.cs.uiuc.edu (128.174.241.10).  The documentation and some
> examples that come with it, show how to create and use PERT charts.

Do you happen to remember what directory HotDraw is in on that
machine?  


--
Steven Litvintchouk
MITRE Corporation
Burlington Road
Bedford, MA  01730

Fone:  (617)271-7753
ARPA:  sdl@mitre.org
UUCP:  linus!sdl
	"Where does he get those wonderful toys?"
From: hubert@cs.uni-sb.de (Hubert Baumeister)
Newsgroups: comp.lang.smalltalk
Subject: Re: Process scheduling on various platforms in ST80R4.
Date: 14 Apr 92 08:55:57 GMT
Organization: Max-Planck-Institut f"ur Informatik

In article <MSMITH.92Apr13160349@volcano.ma30.bull.com>, msmith@volcano.ma30.bull.com (Mike Smith) writes:
|> 
|> I am writing applications that I want to run on 2 platforms, PC's and
|> Sparc Stations.
|> 
|> I have had no problems except for process scheduling.  In particular
|> the fork message to the BlockClosure class acts differently on each
|> platform.
|> 
|> On the PC, the statement "[some code] fork" returns an instance of
|> Process. On the Sparc, it returns an instance of BlockClosure. I
|> have traced the reason for the difference to the fork method itself.
|> 
|> On the PC, the fork method contains the following code
|> 	^self newProcess resume
|> 
|> on the Sparc it's
|> 	self newProcess resume
|> 
|> Does anyone know the reason for this difference?
|> Also how do I control processes on the Sparc if I can't get a process
|> id.

This behaviour (bug? see below) on a Sparc has been changed in later
releases of the images for the Sparc.  Eg. in the image with identification
code:
         VI 40/0/2/0 40-11-6-4
(obtained with st80 -v st80.im)

You have two choices for fixing this behaviour. The first one is to add the
^ by yourself in the fork method after checking that now one relies on the
return value of the fork method.  (use senders in the browser menu)

The other way is to do it yourself, that is:

proc := [some code] newProcess.
proc resume.

Using proc := [some code] fork may run into problems since it is not sure
!!when!! the assignment takes place. Compare the following two pieces of
code.

| proc |
proc := 'test'.
proc := [Transcript show: proc printString; cr; endEntry]
		 forkAt: Processor activeProcess priority + 1.

| proc |
proc := 'test'.
proc := [Transcript show: proc printString; cr; endEntry] 
		forkAt: Processor activeProcess priority - 1.
(Delay forMilliseconds: 200) wait "This is used to give the process at lower
				priority a chance to run"

	Hubert

-- 
Hubert Baumeister
MPI Informatik, Im Stadtwald, W-6600 Saarbr"ucken, Germany
Phone: (x49-681)302-5432
e-mail: Hubert.Baumeister@mpi-sb.mpg.de
Newsgroups: comp.lang.smalltalk
From: alford@alc.com (Mack Alford)
Subject: ST80 Test Metrics??
Followup-To: comp.lang.smalltalk
Keywords: testing, metrics, smalltalk
Reply-To: alford@alc.com
Organization: Ascent Logic Corporation
Distribution: na
Date: Mon, 13 Apr 1992 20:14:13 GMT

Has  anyone implemented test metric in ST80 (e.g., keep track of the percent of
methods exercised during a sequence of tests, the percent of methods with
distinct parameters,  the percent of "calls", etc)?

Are there any automated aids available to help do this, either home grown or
commercially available??

Feel free to respond here, or email me directly.  I will be glad to summarize
the results. 

Mack Alford
Ascent Logic Corporation
alford@alc.com
From: panu@ajk.tele.fi (Panu Viljamaa)
Newsgroups: comp.lang.smalltalk
Subject: ParcPlace v.2.5 on Powerbook
Date: 13 Apr 92 12:25:06 GMT
Organization: Telecom Finland



ParcPlace  2.5  on Macintosh system 7 ?


I already accomplished to sell a project
by showing a prototype built on Parc Place 2.5.

The target environment is Macintosh Powerbook
which runs the system 7, and I can't get my 
years worth of Smalltalk-code to run there.
(error type 90 !). Now I'm in trouble.

I looked at ParcPlace 4.0 and it seems that to
convert my graph-software based on views, subviews,
WindowingTransformations etc. would require rewriting
most of the software. So I might as well write it
on Digitalk for economic reasons.

It seems that PP4.0 has re-assigned the responsibilities
of classes like view/model/controller to new classes
like 'DependentsComposite',  'Wrapper' etc.

It would seem a good application of  MULTIPLE
INHERITANCE to write the compatibility-classes.
A compatibility class like 'OldStandardSystemView'
would inherit some functionality from 'View'
and some from the new classes like 'Wrapper'. 

Any suggestions ?  Any comments on the
portability offered by OO/Smalltalk  ?

Why couldn't ParcPlace offer a decent
backwards-compatibility package ? I suppose
they would if they could !


- Panu Viljamaa

panu@ajk.tele.fi
From: n9146269@waldorf.cc.wwu.edu (OverLord of Underlings)
Newsgroups: comp.lang.smalltalk
Subject: Digitalk Debugger
Date: 17 Apr 92 17:10:52 GMT
Article-I.D.: waldorf.n9146269.703530652
Organization: Western Washington University

I am trying to modify the debugger in Digitalk's Smalltalk/V 286 and am not
having that much success... can anyone give any advice or suggestions?


-- 
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
RWD
_O_  Ryan Walker Davis >> The HeadHunter >> OverLord of Underlings
 |   n9146269@henson.cc.wwu.edu
Newsgroups: comp.lang.smalltalk
From: ian@syacus.acus.oz.au (Ian Joyner)
Subject: C++ Critique in comp.lang.c++
Organization: ACUS Australian Centre for Unisys Software, Sydney
Date: Wed, 8 Apr 1992 12:11:37 GMT

I have placed a critique of C++ in comp.lang.c++. As the comparison of C++
and Smalltalk is often raised, this may be of interest.
-- 
Ian Joyner                                     ACSNet: ian@syacus.acus.oz
ACUS (Australian Centre for Unisys Software)   Internet: ian@syacus.acus.oz.au
Tel 61-2-390 1328      Fax 61-2-390 1391       UUCP: ...uunet!munnari!syacus.oz
Newsgroups: comp.lang.smalltalk
From: gessel@cs.swarthmore.edu (Daniel Mark Abrahams-Gessel)
Subject: How to get Quadra update for Smalltalk/V
Organization: Swarthmore College
Date: Tue, 14 Apr 1992 18:01:20 GMT


I received this via email recently in response to my original article, and 
was asked to post it.  Hope this helps anybody who hasn't gotten their 
update yet.

Dan



Quadra Problem for Smalltalk/V Mac Corrected - free update available

If you are a registered user of Smalltalk/V Mac and are having problems with
running on a Quadra, please contact us at DIGITALK and provide your serial
number.  We'll send you an update free of charge.

There are three ways you can get your update (do not reply to the poster of
this article, that's guaranteed not to work):

1.  Give us a call (it's almost like being there :-).  Our telephone number
is (213) 645-1082.  Just tell us you're interested in the Quadra update for
Smalltalk/V Mac and have your serial number handy.

2.  E-mail your name, address, phone number and serial number to
Quadra_Update@instance.com.  We'll send you the update via hard mail.

3.  You can also download the update via a private forum on Compuserve. 
Send your serial number to 71361,1636 to access it.

Despite allegations to the contrary in this newsgroup we do really do want
to keep our customers happy!

p.s. Thanks (really) to those complaining on the net about their
difficulties in obtaining the update.  I try to keep up on this newsgroup,
so your protests do not always fall on deaf ears...

Tim O'Connor
DIGITALK
From: wallingf@pleiades.cps.msu.edu (Eugene Wallingford)
Newsgroups: comp.lang.smalltalk
Subject: Re: Smalltalk/V on Quadra
Date: 9 Apr 92 16:55:35 GMT
Distribution: na
Organization: Department of Computer Science, Michigan State University

>Smalltalk/V does not work on the Quadra, period.

     Does ParcPlace Objectworks run on the Quadra?

>There just is not enough competition in the Smalltalk market;  I am
>beginning to think it will never really be accepted because neither
>ParcPlace or Digitalk seems to want to supply the workaday tools that
>serious developers need.

     Just out of curiosity (I am getting ready to spend $$ to get PP
     O'Works), what sorts of intransigence has ParcPlace shown?  I've
     been happy so far, but have not yet struck out on my own with the
     package.

-- 
~~~~ Eugene Wallingford             ~~~~   AI/KBS Laboratory         ~~~~
~~~~ wallingf@pleiades.cps.msu.edu  ~~~~   Michigan State University ~~~~
From: msmith@volcano.ma30.bull.com (Mike Smith)
Newsgroups: comp.lang.smalltalk
Subject: Re: Query on PERT chart and/or box/line drawing/editing tools
Date: 8 Apr 92 19:10:03 GMT
Organization: Bull HN, Worldwide Information Systems, Billerica, Mass., USA

In article <1992Apr7.215013.890@sequent.com> rbk@sequent.com (Bob Beck) writes:

  We have a project starting in Smalltalk80 (ParcPlace) and may need to be able
  to draw/edit things like PERT charts.  Does anyone have, or have a pointer
  to, such tools?  If not PERT charts, then assistance with tools that can draw
  and edit boxes connected with lines would be very helpful.

  I'm interested in freeware *or* forSaleWare.  Thanks in advance for all
  information!
  -- 
  Bob Beck			rbk@sequent.com
  Sequent Computer Systems	(503)578-9809


I just finished looking over a tool called HotDraw.  It is archived
at speedy.cs.uiuc.edu (128.174.241.10).  The documentation and some
examples that come with it, show how to create and use PERT charts.

good luck!
Mike

--
-----------------------------------------------------------------------

    Mike Smith                       Bull HN Information Systems Inc.
    (508) 294-2049                   300 Concord Road  MA30 826A
    M.Smith@bull.com                 Billerica, MA 01821  USA

-----------------------------------------------------------------------
From: rbk@sequent.com (Bob Beck)
Newsgroups: comp.lang.smalltalk
Subject: Query on PERT chart and/or box/line drawing/editing tools
Date: 7 Apr 92 21:50:13 GMT
Article-I.D.: sequent.1992Apr7.215013.890
Organization: Sequent Computer Systems Inc.

We have a project starting in Smalltalk80 (ParcPlace) and may need to be able
to draw/edit things like PERT charts.  Does anyone have, or have a pointer
to, such tools?  If not PERT charts, then assistance with tools that can draw
and edit boxes connected with lines would be very helpful.

I'm interested in freeware *or* forSaleWare.  Thanks in advance for all
information!

-- 
Bob Beck			rbk@sequent.com
Sequent Computer Systems	(503)578-9809
From: sobol@watoga.cerc.wvu.wvnet.edu (Michael Sobolewski)
Newsgroups: comp.lang.smalltalk
Subject: drag and drop
Keywords: direct manipulation, GUI
Date: 16 Apr 92 16:29:12 GMT

Where can I find FAQ of this newsgroup?

Does anybody have sources for ST80R4 classes 
to support drag and drop between ST views.

If anyone could mail these classes 
or the ftp side where such clasesse can be found,
it would be greatly appreciated.

Mike 

-------------------------------------------------------------------------------
Michael Sobolewski              How not to get lost in the complexities of our 
CERC/WVU, Drawer 2000           own making is still computing's core challenge.
Morgantown, WV 26506                                           Edsger Dijsktra
office: (304) 293-6961
e-mail: sobol@cerc.wvu.wvnet.edu
From: steven@monu6.cc.monash.edu.au (Steve Stergakis)
Newsgroups: comp.lang.smalltalk
Subject: INFO NEEDED on OOA Methodologies
Date: 8 Apr 92 09:49:55 GMT
Organization: Monash University, Caulfield Campus


NOTE: this message has been posted for persons that either use, teach 
or have some opinion regarding current OOA methodologies being 
used...

THIS MESSAGE HAS BEEN CROSS POSTED TO MANY NEWS GROUPS.  PLEASE 
DISREGARD IT IF HAS BEEN POSTED TO AN INCORRECT AREA.

i am a postgraduate student who is currently studying OOA and 
would greatly appreciate any information regarding experience
you have had with object oriented methodologies

as i am about to write a critical review of the current OO methodologies i 
would appreciate if you could tell me which approach you prefer.. or if
you know of any article that have compared current OOA methods, that would
also be greatly appreciated...

i am especially interested in persons who use such methodologies 
in practice.. their extent of their use in your work area.. 
the type of work you do.... and your opinion!

PLEASE feel free to comment on any of the above questions.. if you do
not wish to relate specific information pertaining to your work /
work environment, then leave it out

NOTE: if possible please reply directly to me 

thanks in advance

+------------------------------------------------------------+
| Steven Stergakis      steven@monu6.monash.cc.edu.au        |
|                                                            |
|                       (Post Graduate)                      |
|                       Faculty of Computing and Information |
|                       Technology                           |
|                                                            |
|                       Monash University - Australia        | 
+------------------------------------------------------------+
Newsgroups: comp.lang.smalltalk
From: muhr@opal.cs.tu-berlin.de (Thomas Muhr)
Subject: Is this a DigiBug?
Organization: Techn. University of Berlin, Germany
Date: Thu, 16 Apr 1992 19:29:30 GMT

Object-oriented design includes easyness of rearranging designs during all
phases of development. But this paradigm is not always very well supported by
DigiTalk's ST/V 286: If you prune and graft a subtree by first removing all
instances of all classes about to be moved, then file out the subtree, then
remove all the classes, then edit the filout to determin the new node under
which the subtree is to be connected, then file in the modified sources - 
you are in trouble:
All methods anywhere in the system which reference classes included in the
move have to be recompiled manually, otherwise you will have lots of "not
understood" errors by messages directed to an instance of DeletedClass.
You can imagine that you may even not have a chance to do this recompilation
if you have moved something like Menu. Well, what to do: Make a global search
through all classes for occurences of any of the class names involved. Make
a senseless modification to every method found in this search and "save" it.
Without a modification, "save" will not work!
I have modified the MethodBrowser so that all methods found in the search can
be recompiled with one click.
Well, why is this not fully supported by the language vendor, including "prune
& graft" in the class browsers menu? I don't know PPS well enough, but I bet
they have such "goodies" (better say "neccessities") included!
If there is interest I can post the code to recompile within a MethodBrowser.
- Thomas 
--
Thomas Muhr - Project ATLAS - Technical University of Berlin
voice: (xx49) (030) 314 27882  
INTERNET: muhrth@db0tui11.bitnet
UUCP: muhr@opal.cs.tu-berlin.de
From: johnson@m.cs.uiuc.edu (Ralph Johnson)
Newsgroups: comp.lang.smalltalk
Subject: Re: ParcPlace v.2.5 on Powerbook
Date: 13 Apr 92 13:41:43 GMT
Organization: University of Illinois, Dept. of Comp. Sci., Urbana, IL

panu@ajk.tele.fi (Panu Viljamaa) writes, after complaining about the
fact that 4.0 will require him to rewrite a lot of a system that he
built in 2.5:

>Why couldn't ParcPlace offer a decent
>backwards-compatibility package ? I suppose
>they would if they could !


I sympathise with Panu.  Lots of other people have been suffering
from the same problems.   However, MVC needed to be rewritten badly,
and though he is going to suffer the agonies of coverting to a new
standard, people in the future will enjoy the benefits of an elegant
and powerful user interface system.

This is a general problem with reusable software.  The first systems
that are built will not be the best, because people will keep thinking
up better ways to solve the problem.  Eventually the time will come
to throw out the old system and make a better one.  ParcPlace tried
to make the new system as compatible with the old as they could, so
simple text-based browsers can be changed easily.  However, the graphics
model is much, much better, and completely different, so programs that
use a lot of graphics are hit hard.

The more I have learned 4.0, the more I have realized that it follows
the same spirit as the original MVC, and in part is just a much better
incarnation of that spirit.  If you make sure that you learn 4.0 first,
and not try to convert something piecemeal as a way to learn 4.0,
you will probably find that conversion is not as hard as you thought
at first.

-Ralph Johnson
Newsgroups: comp.lang.smalltalk
From: muhr@opal.cs.tu-berlin.de (Thomas Muhr)
Subject: Re: Smalltalk V/Windows problem -- errors starting
Organization: Techn. University of Berlin, Germany
Distribution: fb20
Date: Tue, 14 Apr 1992 07:28:18 GMT

anthony@zone4.ocunix.on.ca (Anthony Lander) writes:

>In article <1992Apr11.132552.14885@ctr.columbia.edu> david@osage.ctr.columbia.edu (David Friedlander) writes:
>>
>>I wonder if anyone has solved this problem: 
>>Smalltalk V/Windows, which I gather from this group has lots of bugs.
>>Version 1.0, Windows 3.0.
>>Works fine most of the time.  But not infrequently, upon starting a
You're lucky!
>>new session, the environment does not come up again but instead, a 
>>debug window giving errors from the display classes.  I could recreate
>>The best thing to do is upgrade to version 1.1, which fixes this problem.
>Until then, if you get the red walkback window when you start up, type
>"Notifier reinitialize", select it, and do it.  You can type right in the
>debugging window.

File in this fix provided by Digitalk on their Compu$erve forum:
------ Cut here -----------
"
With version 1.0 and 1.1 of Smalltalk/V Windows, users may occassionally
receive a Walkbalk window upon starting VW, which reports the
following error:

Character(Object) doesNotUnderstood:  asParameter.

To solve this problem, add the following method >>aboutToSaveImage to
the class ListBox:
"

!ListBox methods !

aboutToSaveImage

label := ''.
super aboutToSaveImage. ! !

"This correction will NOT be required in ST/V Windows version 1.2 or later."
    
--
Thomas Muhr - Project ATLAS - Technical University of Berlin
voice: (xx49) (030) 314 27882  
INTERNET: muhrth@db0tui11.bitnet
UUCP: muhr@opal.cs.tu-berlin.de
Newsgroups: comp.lang.smalltalk
From: msmith@volcano.ma30.bull.com (Mike Smith)
Subject: Process scheduling on various platforms in ST80R4.
Organization: Bull HN, Worldwide Information Systems, Billerica, Mass., USA
Date: 13 Apr 92 16:03:49


I am writing applications that I want to run on 2 platforms, PC's and
Sparc Stations.

I have had no problems except for process scheduling.  In particular
the fork message to the BlockClosure class acts differently on each
platform.

On the PC, the statement "[some code] fork" returns an instance of
Process. On the Sparc, it returns an instance of BlockClosure. I
have traced the reason for the difference to the fork method itself.

On the PC, the fork method contains the following code
	^self newProcess resume

on the Sparc it's
	self newProcess resume

Does anyone know the reason for this difference?
Also how do I control processes on the Sparc if I can't get a process
id.

Thanks in advance,
Mike

--
-----------------------------------------------------------------------

    Mike Smith                       Bull HN Information Systems Inc.
    (508) 294-2049                   300 Concord Road  MA30 826A
    M.Smith@bull.com                 Billerica, MA 01821  USA

-----------------------------------------------------------------------