9fans - fans of the OS Plan 9 from Bell Labs
 help / color / mirror / Atom feed
* Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
@ 2001-12-13  1:41 Russ Cox
  2001-12-13  1:51 ` Andrew Simmons
  0 siblings, 1 reply; 38+ messages in thread
From: Russ Cox @ 2001-12-13  1:41 UTC (permalink / raw)
  To: 9fans

> The original TeX was written in a language called Web, which tries to
> address some of the limitations of standard Pascal. When the Web source is
> run through a program called Tangle it generates Pascal source code, and
> when run through a program called Weave it generates an allegedly
> attractive and easier to follow version of the program, although I
> personally find the resultant programs virtually impossible to follow.

Suppose you subscribe to the Kernighan & Plauger thesis that
programs should be clear.  Then the fundamental problem here
is that literate programming provides yet another way not to
address a lack of clarity in the program.  If a program doesn't
make sense at first reading, it doesn't need extra text describing
it; it needs a good rewrite.  Too often, people spend their time
documenting a bad program instead of rewriting it into a good
program.  It's been many years since I looked at Knuth's book,
so I'm not claiming this is or is not his problem.  However, I've
worked with enough literate programs in the past couple years
to know that it can be a problem.

On the other hand, if you start with a clear program then I think
literate programming isn't such a bad way to make it accessible
to a larger audience, especially one that isn't experienced in
reading code they didn't write.

> It's all described in Knuth's book "Literate Programming", and the program
> itself can be seen in the book "TeX, The Program". Knuth gave up the Pascal
> version some time ago, and now uses a C version called CWeb.

This is not true.  As Howard said, the Pascal is still very much
there, just converted to C as part of the build process.  If you
don't believe me, try:

	cd /sys/src/cmd/tex/web2c/tex
	/sys/lib/texmf/bin/$cputype/tangle tex.web tex.ch
	sed 20q tex.p

Also, quoted from /sys/src/cmd/tex/web2c/doc/web2c.info-1:

%   "Web2c" is the name of a TeX implementation, originally for Unix, but
% now also running under DOS, Amiga, and other operating systems. By "TeX
% implementation", we mean all of the standard programs developed by the
% Stanford TeX project directed by Donald E. Knuth: Metafont, DVItype,
% GFtoDVI, BibTeX, Tangle, etc., as well as TeX itself. Other programs
% are also included: DVIcopy, written by Peter Breitenlohner, MetaPost
% and its utilities (derived from Metafont), by John Hobby, etc.
%
%   General strategy: Web2c works, as its name implies, by translating the
% WEB source in which TeX is written into C source code. Its output is
% not self-contained, however; it makes extensive use of many macros and
% functions in a library (the `web2c/lib' directory in the sources).
% Therefore, it will not work without change on an arbitrary WEB program.
%
% [...]
%
%   History: Tomas Rokicki originated the TeX-to-C system in 1987,
% working from the first change files for TeX under Unix, which were done
% primarily by Howard Trickey and Pavel Curtis. Tim Morgan then took over
% development and maintenance for a number of years; the name changed to
% Web-to-C somewhere in there.  In 1990, Karl Berry became the
% maintainer.  He made many changes to the original sources, and started
% using the shorter name Web2c.  In 1997, Olaf Weber took over.  Dozens of
% other people have contributed; their names are listed in the
% `ChangeLog' files.

Russ



^ permalink raw reply	[flat|nested] 38+ messages in thread
* Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
@ 2001-12-14 11:15 forsyth
  0 siblings, 0 replies; 38+ messages in thread
From: forsyth @ 2001-12-14 11:15 UTC (permalink / raw)
  To: 9fans

[-- Attachment #1: Type: text/plain, Size: 440 bytes --]

not really, it just takes time to do all these things and there
are more urgent things to do.  i've got a fairly big list myself.
meanwhile, we've all still got opinions about these things.
some of us fitfully post them as a form of displacement activity
when we should be working away at those lists...
actually, i'd probably prefer porting my Pascal compiler
to Plan 9 to working on Inferno's PPP set up but it can't be all fun.


[-- Attachment #2: Type: message/rfc822, Size: 2955 bytes --]

To: 9fans@cse.psu.edu
Subject: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
Date: Fri, 14 Dec 2001 10:14:54 GMT
Message-ID: <878zc6vo0y.fsf@becket.becket.net>

"Douglas A. Gwyn" <DAGwyn@null.net> writes:

> "Thomas Bushnell, BSG" wrote:
> > "Douglas A. Gwyn" <DAGwyn@null.net> writes:
> > > D De Villiers wrote:
> > > > No Pascal implementation ? Pascal compiler etc etc ?
> > > Why?  What use would it be?
> > It would let you run Pascal programs.
>
> And what use would *that* be?
> Seriously, are there any major apps written in Pascal?

Um, TeX, as has already been noted.  I think Pascal is a pointless
silly language, myself.

But still--even if there are misguided people who want to use it for
teaching, the availability of a compiler makes a system more
attractive to those people.

It seems this discussion is of a schema that is very common on this
newsgroup:

A: Why doesn't Plan 9 have a fritz-widget?
B: A fritz-widget is useless.
A: Lots of people like fritz-widgets.
B: Those people are misguided.
A: But I want to use the wooble application, and it requires
   fritz-widgets.
B: The wooble application is a bad application.
A: What does Plan 9 have to do the things that the wooble application
   is for?
B: No.
A: Hmm.

[some time later]

B: I wonder why Plan 9 hasn't caught on more than it has.  Maybe it's
   because people reject our brilliance.

Thomas

^ permalink raw reply	[flat|nested] 38+ messages in thread
* Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
@ 2001-12-13 21:52 bwc
  2001-12-13 23:57 ` Andrew Simmons
  0 siblings, 1 reply; 38+ messages in thread
From: bwc @ 2001-12-13 21:52 UTC (permalink / raw)
  To: 9fans

[-- Attachment #1: Type: text/plain, Size: 653 bytes --]

On the subject of Pascal, you really need to look at Oberon.
Niklaus Wirth continued to evolve Algol after Pascal.
Oberon is a real language, and it overcomes all of Kernighan's
objections to Pascal.  (All except the ones that have now been
put into C, like defining procedures before referencing them).

Oberon has many of the desirable traits of Limbo; compile and runtime
typechecking, garbage collection.  It compiles into native code so it
executes faster for embedded stuff (what I do).

Also, it inspired acme.  (the Oberon OS, not the language)

I hope to have Oberon running on Plan 9 someday in the distant
future.

  Brantley

[-- Attachment #2: Type: message/rfc822, Size: 1622 bytes --]

From: David Gordon Hogan <dhog@plan9.bell-labs.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
Date: Wed, 12 Dec 2001 16:50:47 -0500
Message-ID: <20011212215052.F2DE7199ED@mail.cse.psu.edu>

> > Why?  What use would it be?
>
> Writting software ! <G> What * use * else...

I've never found Pascal to be particularly useful
for writing software.  I understand that it was
originally intended for teaching purposes, but
there are some tasks which are so difficult to
do correctly with Pascal that you have to learn
how to program again when you start using a
real language, like C.

And then there's Basic...

^ permalink raw reply	[flat|nested] 38+ messages in thread
* Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
@ 2001-12-13  4:25 rob pike
  0 siblings, 0 replies; 38+ messages in thread
From: rob pike @ 2001-12-13  4:25 UTC (permalink / raw)
  To: 9fans

When I worked in Switzerland I used Pascal on the 7600 at ETH, Klaus's
very compiler on Klaus's very machine.  It was a fascinating exercise
because I learned a great deal about why Pascal, particularly Pascal
I/O, is so bizarre.  It has to with generalities and even I think a
few local specifics of the operating system Control Data installed on
this particular machine.  When the input is a card deck and you can
always see if the next card is $EOF$ (or something like that), the
handling of EOF on a terminal is far from your mind and Pascal's
nextln and all that almost seems OK.

In that weird world, Pascal I/O made sense to me, but in no other.

-rob



^ permalink raw reply	[flat|nested] 38+ messages in thread
* Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
@ 2001-12-13  4:05 rob pike
  2001-12-13 10:27 ` Ozan Yigit
                   ` (2 more replies)
  0 siblings, 3 replies; 38+ messages in thread
From: rob pike @ 2001-12-13  4:05 UTC (permalink / raw)
  To: 9fans

I thought the original TeX was written in SAIL.

-rob



^ permalink raw reply	[flat|nested] 38+ messages in thread
* Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
@ 2001-12-12 22:43 forsyth
  0 siblings, 0 replies; 38+ messages in thread
From: forsyth @ 2001-12-12 22:43 UTC (permalink / raw)
  To: 9fans

[-- Attachment #1: Type: text/plain, Size: 954 bytes --]

it was intended -- and used -- for more than just teaching, but
unfortunately even the ISO Standard Pascal language does not provide
portable ways of accessing system functions of post-mainframe
operating systems (even interactive i/o might not be provided).
consequently there are a great many dialects and specialised
extensions.  Standard Pascal is a small language that is fairly easy
to implement though.

on the other hand, ISO Extended Pascal still doesn't provide portable
ways of doing many of the things missing from Standard Pascal either,
but it's not small.  It began as a simple and achievable standards
committee project to add 4 or 5 obvious and simple extensions to
Standard Pascal, to address the most common portability problems
(opening an external file named interactively, for instance), but it
took on a life of its own.  (i bequeathed my copy of the resulting huge stack of
paper to the university when i left.)


[-- Attachment #2: Type: message/rfc822, Size: 1795 bytes --]

To: 9fans@cse.psu.edu
Subject: Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
Date: Wed, 12 Dec 2001 16:50:47 -0500
Message-ID: <20011212215052.F2DE7199ED@mail.cse.psu.edu>

> > Why?  What use would it be?
>
> Writting software ! <G> What * use * else...

I've never found Pascal to be particularly useful
for writing software.  I understand that it was
originally intended for teaching purposes, but
there are some tasks which are so difficult to
do correctly with Pascal that you have to learn
how to program again when you start using a
real language, like C.

And then there's Basic...

^ permalink raw reply	[flat|nested] 38+ messages in thread
* Re: [9fans] Re: Plan9 Programming languages ! -- PASCAL?
@ 2001-12-12 21:50 David Gordon Hogan
  2001-12-12 22:54 ` paurea
  0 siblings, 1 reply; 38+ messages in thread
From: David Gordon Hogan @ 2001-12-12 21:50 UTC (permalink / raw)
  To: 9fans

> > Why?  What use would it be?
>
> Writting software ! <G> What * use * else...

I've never found Pascal to be particularly useful
for writing software.  I understand that it was
originally intended for teaching purposes, but
there are some tasks which are so difficult to
do correctly with Pascal that you have to learn
how to program again when you start using a
real language, like C.

And then there's Basic...



^ permalink raw reply	[flat|nested] 38+ messages in thread
* [9fans] Plan9 Programming languages !
@ 2001-12-06 17:13 D De Villiers
  2001-12-10 10:01 ` [9fans] Re: Plan9 Programming languages ! -- PASCAL? D De Villiers
  0 siblings, 1 reply; 38+ messages in thread
From: D De Villiers @ 2001-12-06 17:13 UTC (permalink / raw)
  To: 9fans

Hello!

I just got my first copy of Plan9 - I am a software developer/programmer and
wanna know what languages are there avialable for Plan9 development? Any
Delphi/Pascal, Java, Perl implementation etc ? (only know about C language).

Regards,

Lennie De Villiers

--- Remove ~ and 9s from e-mail address to reply ---


^ permalink raw reply	[flat|nested] 38+ messages in thread

end of thread, other threads:[~2002-01-02 11:31 UTC | newest]

Thread overview: 38+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2001-12-13  1:41 [9fans] Re: Plan9 Programming languages ! -- PASCAL? Russ Cox
2001-12-13  1:51 ` Andrew Simmons
2001-12-13  1:55   ` Andrew Simmons
  -- strict thread matches above, loose matches on Subject: below --
2001-12-14 11:15 forsyth
2001-12-13 21:52 bwc
2001-12-13 23:57 ` Andrew Simmons
2001-12-13  4:25 rob pike
2001-12-13  4:05 rob pike
2001-12-13 10:27 ` Ozan Yigit
2001-12-13 13:39 ` Thomas Bushnell, BSG
2001-12-13 19:39 ` Andrew Simmons
2001-12-13 20:28   ` Matt
2001-12-12 22:43 forsyth
2001-12-12 21:50 David Gordon Hogan
2001-12-12 22:54 ` paurea
2001-12-12 23:16   ` Howard Trickey
2001-12-12 23:23   ` Dan Cross
2001-12-13  0:55   ` Andrew Simmons
2001-12-13 11:54   ` Boyd Roberts
2001-12-06 17:13 [9fans] Plan9 Programming languages ! D De Villiers
2001-12-10 10:01 ` [9fans] Re: Plan9 Programming languages ! -- PASCAL? D De Villiers
2001-12-11 10:07   ` Douglas A. Gwyn
2001-12-12  9:48     ` Thomas Bushnell, BSG
2001-12-13 10:26       ` Douglas A. Gwyn
2001-12-13 12:04         ` Wladimir Mutel
2001-12-14 10:15           ` Douglas A. Gwyn
2001-12-14 10:14         ` Thomas Bushnell, BSG
2001-12-14 17:04           ` Douglas A. Gwyn
2001-12-17 10:15             ` Thomas Bushnell, BSG
2001-12-14 17:37         ` D De Villiers
2001-12-17 10:14         ` Daniel Warmuth
2001-12-18 17:27           ` D De Villiers
2001-12-18 19:35             ` Matt
2001-12-12 17:12     ` D De Villiers
2001-12-14 10:15       ` north_
2002-01-02 10:04   ` kim kubik
2002-01-02 11:12     ` mark powers
2002-01-02 11:22     ` Jon Snader
2002-01-02 11:31     ` Ralph Corderoy

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).