HDTenEightyP/NetNews huggingface dataset:
From: mfeldman@seas.gwu.edu (Michael Feldman)
Subject: Compiler errors vs. runtime behavior
Organization: George Washington University
Date: Sun, 13 Dec 1992 20:29:38 GMT

In article <921212103914.20203764@OTTAWA.DSEG.TI.COM> PETCHER@OTTAWA.dseg.ti.com (What? Me Ada?) writes:
>
>I would submit that neither of these warnings is completely correct for this
>particular example, at least without further qualification.  'x' is, in fact,
>used after assignment, although both the assignment and the subsequent use
>could be optimized away.  If they are, the compiler should state that in the
>warning.  If not, no warning should be given.  If you really put the
>offending semicolon in by accident, but the program compiled OK anyway, even
>with the warning, you'd say "Of course it's used.  Compiler bug." then get in
>there with a debugger and wonder why you couldn't find 'x' or any code
>associated with it.  The warning about the infinite loop should only be given
>if the compiler supports the "volatile" storage class modifier.  Most do, and
>I think the ANSI standard requires it, but not all compilers support it just
>the same, or just ignore it.  The result is something outside the current
>context could change the value of x and terminate the loop.

All of which shows just how subjective - and therefore controversial -
is the whole area of compiler warnings, or advisories, or whatever, that
go beyond detection of compile-time errors. Even error _repair_ - so that
the compiler does not have to bail out on the first error - is a bit
dicey, because the repair is so often wrong.

The point of my post about the C semicolon _accidentally_
causing an infinite loop with a single keystroke error, and the 
preceding post about the Fortran comma-vs.-error, is that we ought to
design our languages so that the probability of this kind of error is
minimized. This is done by building enough redundancy into the syntax
(using e.g. fully-bracketed control structures, Ada's use of which is
_horribly_ verbose to many C folks) so that what would otherwise be an
undetectable runtime error is turned into an easily detectable
compile-time error. This is the whole point of verbose (OK, I'll
use the nay-sayers' term) strongly-typed languages. 

The only comparable case in Ada is the ";" vs. "IS" problem, which
leads to confusing compilation errors but at least it doesn't cause
obscure run time behavior.

Once again we come back to undebatable matters of taste: one person's
verbosity is another's safety-enhancing redundancy (fault tolerance, if
you will). Would you rather debug at compile time or run time?

Cheers -

Mike Feldman
------------------------------------------------------------------------
Michael B. Feldman
co-chair, SIGAda Education Committee

Professor, Dept. of Electrical Engineering and Computer Science
School of Engineering and Applied Science
The George Washington University
Washington, DC 20052 USA
(202) 994-5253 (voice)
(202) 994-5296 (fax)
mfeldman@seas.gwu.edu (Internet)

"Americans want the fruits of patience -- and they want them now."
------------------------------------------------------------------------
Newsgroups: comp.lang.ada
From: ulf@julius.c3consult.comm.se (Ulf Lagerstedt)
Subject: Inventory of methods for software development
Organization: Communicator C3Consult AB
Distribution: comp
Date: Thu, 17 Dec 1992 16:38:08 GMT



 (I asked this a while ago in comp.software.eng, with limited success.
 If the subject is slightly inappropriate for this newsgroup, I apologize.
 I urge you to mail your answers. Thanks.)


I am about to do a survey or inventory of methods for software development.
With methods, I mean documented procedures and conceptual models for
either the entire development process or some parts thereof.

Anything worth being called a method in this sense is of interest.
Obviously, a complete inventory would be very large, but I hope
to be able to compile information about at least a large share of
the more widespread methods.

I wish to get as much information as possible about each method,
but the following will do fine:

                                                (for instance)

Name:                                           Coad/Yordon OOA and OOD
Key characteristics:                            Object oriented
Parts of development process concerned:         Analysis, design
Software tools supporting the method:           ...etc.
Result/output from method:
References:
- Documentation (title, author, etc):
- Organizations (commercial or other):


Please, if you have any references to a particular method, or if you
know of similar work elsewhere, mail me a reply. If there is enough
interest, I'll gladly post a summary. Your help is appreciated.

--
Ulf Lagerstedt, Communicator C3Consult, Sweden  /  ulf@c3consult.comm.se
Newsgroups: comp.lang.ada
From: mccall@mksol.dseg.ti.com (fred j mccall 575-3539)
Subject: Re: Lets split comp.lang.ada into multiple groups to confine flames
Organization: Texas Instruments Inc
Date: Thu, 17 Dec 1992 17:19:42 GMT

In <62879@mimsy.umd.edu> alex@cs.umd.edu (Alex Blakemore) writes:

>In article <BzCs15.B28@gdls.CSCTMD.COM> tarcea@gdls.CSCTMD.COM (Glenn Tarcea) writes:
>>   Can we please stay on the topic of discussing Ada, and Ada in
>> real-world systems. All languages have their strengths and weaknesses
>> and I am tired of hearing religous comparisons of why either Ada is
>> better than language X or language X is better than Ada. Maybe a news
>> group called comp.lang.religion should be started for these stupid discussions. 

>good posting, but how about a real division-

>make comp.lang.ada obsolete and create a small set of groups instead.

>  some suggestions

>    comp.lang.advocacy   - for the flame wars
>    comp.lang.programmer - for discussions of design/development Ada language issues
>                           (or comp.lang.technical or better name?)
>    comp.lang.announce   - moderated, low volume important announcements
>                           of meetings, products, standards, new mandates :) etc
>    comp.lang.misc       - catch all

Uh, I think you're probably going to have some problems getting this
past all the other language groups, since it seems to assume that
'comp.lang.programmer' assumes Ada.  Now, I can't speak for anyone
else, but I'm SURE I've programmed computers in other languages
besides Ada.

Now, I might vote for a comp.lang.announce, but I don't know that I
would want someone dedicated to ANY language 'moderating' it.  Once
again, it assumes that 'comp.lang' equates to 'comp.lang.ada'.  I
suspect this is a real bad assumption.

-- 
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.
Newsgroups: comp.lang.ada
From: mccall@mksol.dseg.ti.com (fred j mccall 575-3539)
Subject: Re: FORTRAN bug(was Re: C++ vs. Ada -- Is Ada loosing?)
Organization: Texas Instruments Inc
Date: Mon, 14 Dec 1992 17:04:21 GMT

In <1992Dec11.213147.24000@seas.gwu.edu> mfeldman@seas.gwu.edu (Michael Feldman) writes:

>In article <1992Dec11.132942.24054@mksol.dseg.ti.com> mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes:
>>
>>>For 10 points on your grade: what is printed? Why?
>>>Try explaining it to a freshman.
>>
>>Nothing is printed.  You built an infinite loop.  This is hard to
>>understand?  You made a while loop with an empty body and a condition
>>that is never met because you never increment x.  Your freshmen don't
>>get this?

>Sure they get it. I just don't want to take my time or theirs on this
>kind of silliness. Which is why I keep saying that C should be
>everyone's second language and nobody's first.

I agree.  I feel the same way about Ada, by the way.  There's simply
too much there to be teaching it to people as a first language.

>>
>>>Any similar idiosyncracies in Ada? 
>>
>>Single character ones?  Probably not, but that just indicates that Ada
>>is incredibly more verbose than C.  One of the things I DISlike about
>>it, by the way.
>>
>You're certainly entitled to your opinion. I'm not down on C. I'd
>rather train my teenager on a nice, verbose, safe car and give him
>the keys to the Porsche after he's proven himself on the Chevy.
>Less chance he'll waste his time crashing and burning. And the 70% or
>more of the freshman teachers who are going to Ada or sticking with
>Pascal (only slightly less verbose than Ada) agree.

Pascal tends to be a somewhat more appropriate choice for a first
language.  It's a nice protected environment with a limited set of
features. 

>Please - no more language wars.

I concur -- which is why I took exception to the original
characterizations of 'the C community'.

-- 
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.
From: SAHARBAUGH@ROO.FIT.EDU
Newsgroups: comp.lang.ada
Subject: Ada does what it says?
Date: 19 Dec 92 23:53:00 GMT
Distribution: world
Organization: The Internet

Pascal writes:
Anyhow this is only one part of the readability. The low-level readability or
instruction readability. I don't mean that an Ada algorithm of many lines will
be easy to understand at the first look. But at least, I think it will be
easy to follow line by line what it does.
An Ada program does what it says.

Pascal.

--
  I suggest this experiment.  Open either volume 1 or volume
2 of Brian and Mendel's book, at random to any page and see
if you can predict the legal conseqence of running any of the
examples they present.  Do this several times and then report
if you you still stand by your statement that "An Ada program does what
it says".
  Their book was a real eye opener to me.  It showed me the folly
of trying to talk to a finite state machine using a textual
language patterned after human natural languages.
sam harbaugh
---
Newsgroups: comp.lang.ada
From: jhb@dale.cts.com (John Bollenbacher)
Subject: Re: FORTRAN bug(was Re: C++ vs. Ada -- Is Ada loosing?)
Organization: Titan Linkabit Corporation
X-Newsreader: Tin 1.1 PL5
Date: Mon, 14 Dec 1992 22:15:31 GMT

God, don't you people ever tire of this?

--
-----------------------------------------------------------------------------
- John Bollenbacher                                        jhb@dale.cts.com -
- Titan Linkabit Corp.                                       (619) 552-9963 -
- 3033 Science Park Rd.                                                     -
- San Diego, Ca. 92121                                                      -
-----------------------------------------------------------------------------
Newsgroups: comp.lang.ada
From: srctran@world.std.com (Gregory Aharonian)
Subject: Was VHDL mentioned at STARS conference?
Organization: The World
Distribution: comp.lang.ada
Date: Wed, 16 Dec 1992 02:49:18 GMT

Could a STARS92 attendee post a note mentioning anyone discussion of VHDL
at the recent STARS Conference?

Greg Aharonian
Source Translation & Optimization
-- 
**************************************************************************
Greg Aharonian
Source Translation & Optimiztion
P.O. Box 404, Belmont, MA 02178
Newsgroups: comp.lang.ada
From: campbell@src.honeywell.com (Terry Campbell)
Subject: Ada/OMG/CFI Bindings
Organization: Honeywell Systems & Research Center
Distribution: comp
Date: Wed, 16 Dec 1992 00:45:49 GMT

I am looking for anyone doing any work on binding Ada to Object Management
Group's CORBA, CAD Framework Initiative framework, ATIS etc.

I am involved with IEEE ABBET standard (A Broad Based Environment for Test
- P1226, used to be called Ada Based Environment for Test).  We are looking
at adopting or developing a standard set of interfaces to object oriented
information management systems based on the EXPRESS object model and want to
see what is going on in terms of binding Ada to real object-oriented 
frameworks.


Terry

---------------------------------------------------------
Terry Campbell                            
Honeywell Systems and Research Center
MN65-2100                  e-mail: campbell@src.honeywell.com            
3660 Technology Dr.        Phone : (612) 951-7517
Minneapolis, MN 55418      Fax   : (612) 951-7438
Newsgroups: comp.lang.ada
From: mfeldman@seas.gwu.edu (Michael Feldman)
Subject: Re: FORTRAN bug(was Re: C++ vs. Ada -- Is Ada loosing?)
Organization: George Washington University
Date: Fri, 18 Dec 1992 21:56:11 GMT

In article <2967.2b31602b@vger.nsu.edu> g_harrison@vger.nsu.edu (George C. Harrison, Norfolk State University) writes:
>In article <1992Dec15.025733.22796@seas.gwu.edu>, mfeldman@seas.gwu.edu (Michael Feldman) writes:
>> In article <Bz9sHv.3B1@dale.cts.com> jhb@dale.cts.com (John Bollenbacher) writes:
>>>God, don't you people ever tire of this?
>>>
>> I do.
>> 
>> Mike
>I do too.  Reminds me of what seventh grade boys do in locker rooms, but I'll
>not take the analogy beyond that.
> 
>George
>
Funny thing, George. Every now and then my wife looks over my shoulder
when I'm reading this group, and she always chuckles at what she calls
"typical male pi**ing contests". She is still waiting to see a female
name on comp.lang.ada (she hasn't lucked into seeing one of Deborah's
posts).

Mike

Newsgroups: comp.lang.ada
From: withrow@lims01.lerc.nasa.gov (Jim Withrow)
Subject: Re: Tired of the Ada vs. (Pick your language) discussion
Organization: NASA Lewis Research Center, Power Systems Facility
Distribution: usa
Date: Thu, 17 Dec 1992 21:11:56 GMT

In article <1992Dec16.213258.23655@saifr00.cfsat.honeywell.com> lam@saifr00.cfsat.honeywell.com (Josh Lam) writes:
>From: lam@saifr00.cfsat.honeywell.com (Josh Lam)
>Subject: Re: Tired of the Ada vs. (Pick your language) discussion
>Date: Wed, 16 Dec 92 21:32:58 GMT
>
>In article <BzCs15.B28@gdls.CSCTMD.COM> tarcea@gdls.CSCTMD.COM (Glenn Tarcea) writes:
>
>
>Glenn>   Can we please stay on the topic of discussing Ada, and Ada in
>Glenn> real-world systems. All languages have their strengths and weaknesses
>Glenn> and I am tired of hearing religous comparisons of why either Ada is
>Glenn> better than language X or language X is better than Ada. Maybe a news
>Glenn> group called comp.lang.religion should be started for these stupid
>Glenn> discussions. I program in both 'C' and Ada and I can appreciate the
>Glenn> strengths (and weaknesses) of each of the languages, I don't need
>Glenn> somebody to give me their supposedly unbiased opinion on language
>Glenn> greatness.
>
>I agree whole-heartly!
>
>Let's make more constructive use of this newsgroup.  Also, its nice to see
>champions of various languages eg Grady Booch and Bjarne Stroustrup working
>and holding conferences together. Let's learn from them and be gracious.
>
>-- 
>Josh Lam
>Honeywell Inc
>lam@saifr00.cfsat.honeywell.com
>

It would be nice to see more discussions on using Ada, and less comparing it 
against ___ language.  Some of us MUST use it, and although it may not 
be the language of choice, it still must be used.
From: g_harrison@vger.nsu.edu (George C. Harrison, Norfolk State University)
Newsgroups: comp.lang.ada
Subject: Re: FORTRAN bug(was Re: C++ vs. Ada -- Is Ada loosing?)
Date: 18 Dec 92 05:22:51 EDT

In article <1992Dec15.025733.22796@seas.gwu.edu>, mfeldman@seas.gwu.edu (Michael Feldman) writes:
> In article <Bz9sHv.3B1@dale.cts.com> jhb@dale.cts.com (John Bollenbacher) writes:
>>God, don't you people ever tire of this?
>>
> I do.
> 
> Mike
I do too.  Reminds me of what seventh grade boys do in locker rooms, but I'll
not take the analogy beyond that.
 
George

Newsgroups: comp.lang.ada
From: eachus@oddjob.mitre.org (Robert I. Eachus)
Subject: Re: I/O and the LRM
Organization: The Mitre Corp., Bedford, MA.
Date: Thu, 17 Dec 1992 16:30:39 GMT

In article <206@hathor.CSS.GOV> jeffe@hathor.CSS.GOV (Jeff Etrick) writes:

 >  I have used the function successfully many times to get the external
 > name of a currently opened file but what I don't understand is the
 > comment about it being used in an open statement. Why would I want to use
 > this statement in an open since the file must already be opened or
 > STATUS_ERROR will be raised.

   Because you might want to close the file and open it again?

   Actually this statement is more of a direction to the implementor
of TEXT_IO than to the user.
--

					Robert I. Eachus

with Standard_Disclaimer;
use  Standard_Disclaimer;
function Message (Text: in Clever_Ideas) return Better_Ideas is...
Newsgroups: comp.lang.ada
From: eachus@oddjob.mitre.org (Robert I. Eachus)
Subject: Re: C++ vs. Ada -- Is Ada loosing?
Organization: The Mitre Corp., Bedford, MA.
	<1992Dec18.141448.13862@mcc.com>
Date: Fri, 18 Dec 1992 21:49:15 GMT

In article <1992Dec18.141448.13862@mcc.com> srogers@teenwolf.mcc.com (Steve Rogers) writes:

   I'm not sure this is true; the Barnes Ada book has LOTS of examples that
   violate the LRM...

   Which edition?  The first edition was published before the ANSI (83)
standard was finalized.  However, it wasn't really Ada 80, more like
81 1/2.

--

					Robert I. Eachus

with Standard_Disclaimer;
use  Standard_Disclaimer;
function Message (Text: in Clever_Ideas) return Better_Ideas is...
From: alex@cs.umd.edu (Alex Blakemore)
Newsgroups: comp.lang.ada
Subject: Re: Suggestion for multivalue boolean case for 9X
Date: 11 Dec 92 20:08:14 GMT
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742

dunbar@saifr00.cfsat.honeywell.com (Mark Dunbar) writes:
> Using Ada83, instead of the nested if statement, one could do the following:
>   if    ( not Cond_1 ) and ( not Cond_2 ) and ( not Cond_3 ) then
>   elsif ( not Cond_1 ) and ( not Cond_2 ) and (     Cond_3 ) then
>   elsif ( not Cond_1 ) and (     Cond_2 ) and ( not Cond_3 ) then
>   etc.

I've rarely encountered complex nested if statements where
every combination of conditions had a completely different action.
More often, several combinations share the same action, or parts of
the same action.  In such cases, you can frequently improve things
by combining and reordering tests - often removing a level of nesting.

for a simple example,

  if x then                               if not x then
    if y then        can be rewritten       C;
      A;                                  elsif y then
    else                                    A;
       B;                                 else
    end if;                                 B;
  else                                    end if;
    C;
  end if;

(assuming the conditions are free of side effects)
A single level chain of ordered condition/action pairs is
much easier to reason about than any nested logic.

I know it seems to picayune but I've found many errors
by simplifying logical statements in mechanical ways
like this - and almost always obtain a better understanding
of the code as a side effect.

This should be ingrained after CS 101 and not be worth mentioning
in such an esteemed forum as comp.lang.ada but many
programmers dont seem to take the time to find the the
simplest construct.



-- 
---------------------------------------------------
Alex Blakemore alex@cs.umd.edu   NeXT mail accepted
Newsgroups: comp.lang.ada
From: orville%weyrich@uunet.uu.net (Orville R. Weyrich)
Subject: Looking for a good speaker for conference
Reply-To: uunet.uu.net!weyrich!orville
Organization: Weyrich Computer Consulting
Distribution: usa
Date: Thu, 17 Dec 92 02:18:54 GMT

I am on the program committee for the 2nd Annual Arizona Business and 
Computer Exhibition which is presented jointly with the 34th Annual
Association for Systems Management Southwest Systems Conference
[March 15-16, Phoenix, AZ].

I would really like to find a speaker to present a technical talk on 
Ada-9X, object-oriented techniques in Ada, and perhaps "mainstreaming" Ada.

The program this year is shaping up to have a lot of very good 
people in the areas of Real-Time, Object-Oriented Systems Modeling
and possibly Object-Oriented Databases and I would like to find someone 
that could give a good technical presentation on the above Ada topic[s].

So, does anyone know of any good speakers/topics that you have heard
that I might try to contact? 

Note: we aren't looking for a sales presentation -- we are looking for a
technical presentation that would enhance our conference. But we have an
exhibit area that we would love to get more vendors for :-)

Any leads (or offers) would be most welcome,

Thanks,


orville

--------------------------------------           ******************************
Orville R. Weyrich, Jr.                           Weyrich Computer Consulting
Certified Data Processor                         POB 5782, Scottsdale, AZ 85261
Certified Systems Professional                        Voice: (602) 391-0821
Internet: orville%weyrich@uunet.uu.net                Fax:   (602) 661-0660
--------------------------------------           ******************************
Newsgroups: comp.lang.ada
From: mfeldman@seas.gwu.edu (Michael Feldman)
Subject: IBM Compiler for VM is in the Dec 92 compiler list
Organization: George Washington University
Date: Thu, 17 Dec 1992 18:27:05 GMT

Just to set the record straight: the December 1992 list of validated
compilers shows IBM compilers for both VM and MVS, in a fairly large
number of different configurations of 370-family hosts and targets.

I have been in contact with a person at IBM Toronto, where the Ada
compilers are handled; he confirms the continued availability of
compilers for both mainframe operating systems.

Naturally they have RS-6000/AIX compilers as well...

Mike Feldman
------------------------------------------------------------------------
Michael B. Feldman
co-chair, SIGAda Education Committee

Professor, Dept. of Electrical Engineering and Computer Science
School of Engineering and Applied Science
The George Washington University
Washington, DC 20052 USA
(202) 994-5253 (voice)
(202) 994-5296 (fax)
mfeldman@seas.gwu.edu (Internet)

"Americans want the fruits of patience -- and they want them now."
------------------------------------------------------------------------
Newsgroups: comp.lang.ada
From: koehnema@enuxha.eas.asu.edu (Harry Koehnemann)
Subject: Re: FORTRAN bug(was Re: C++ vs. Ada -- Is Ada loosing?)
Followup-To: comp.lang.ada
Reply-To: koehnema@enuxha.eas.asu.edu (Harry Koehnemann)
Organization: Arizona State University
Date: Wed, 16 Dec 1992 16:47:12 GMT

In article <1992Dec14.183326.27689@newshost.lanl.gov> jlg@cochiti.lanl.gov (J. Giles) writes:
>|> Michael Feldman:
>|>    ...
>|>    x = 1;
>|>    while (x <= 10);
>|>    { 
>|>       printf("%d\n", x);
>|>       x++;
>|>    }
>Without explicitly looking for the above type of error, or having
>an automated tool which looks for it on your behalf, this could be
>a difficult to find error.  The problem is that programmers look
>at code and *know* what it's supposed to do.  They tend to skim
>the code looking for glaring errors. They miss this sort of thing
>because it's next to invisible.

But, that skimming process is a good thing -  it's a way of using
abstraction.  I don't concern myself with the details of each statement,
rather I abstract out the function of a set of statements.  Another
problem is that a programmer is usually thinking in terms of the problem
domain rather than in terms of the language, which makes it harder
to locate these little language flukes.  Abstraction is an important
tool, but can stab you in the back when you're not looking.

I've seen the above example on many exams and have always had mixed
emotions about it.  Sure it tests the knowledge of the language, but
it's not encouraging the abstraction concepts taught in the class and
may actually be counterproductive.

Another great test question:

	i = 1;
	while (i <= 10)
	    printf("%d\n");
	    i++;

What's the output?  The indentation is a pattern we recognize and it's
easy to "skim" over it and assume we understand something we don't.

For what it's worth.
--
Harry Koehnemann			Arizona State University
koehnema@enuxha.eas.asu.edu		Computer Science Department