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Re: for or against equality, was Why are ambiguous grammars usually a bad idea?

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On 04/01/2022 21:26, gah4 wrote:
> Stories are that COBOL programmers always
> keep the list of reserved words nearby, to avoid using them.

Our esteemed moderator claims:
> [COBOL doesn't have that many reserved words

I count 510 reserved words in IBM COBOL. Adding a few other dialects
can push the total to 700 or more. By comparison, C has about 32
reserved words.

The story I heard was of a COBOL shop where it was mandatory to
include a hyphen in every data name: in effect, *every* unhyphenated
word was treated as a reserved word. The slightly more managable list
of *hyphenated* reserved words (149 in IBM COBOL, but 46 of these are
of the form COMP-0, COMP-1, COMP-2 etc) was printed out and posted on
the wall.

I just noticed that if you include a digit in the part of the name
before the first hyphen, you can guarantee to avoid all
the reserved words!

PL/I went to the other extreme of no reserved words in reaction
to COBOL. Also, the aim of PL/I was to be a language which does
everything: business programming (like COBOL) and scientific
programming (like FORTRAN). In theory, if you only wanted
to do, say, business programming, you only needed to learn
part of the language and you would not get tripped up by keywords
from the other part of the language that you didn't know about yet.

Using a language that you don't know in its entirety might seem
dangerous, but everybody seems to do it these days:
how many C programmers have read the entire 500+ pages of
the latest C standard and memorised the 200+ varieties
of "undefined behaviour" so that they can avoid all of them
in every line of code that they write?
--
			Martin

Dr Martin Ward | Email: martin@gkc.org.uk | http://www.gkc.org.uk
G.K.Chesterton site: http://www.gkc.org.uk/gkc | Erdos number: 4
[IBM hoped everyone would switch from Fortran and COBOL to PL/I and
it was obvious Fortran programmers would not put up with reserved
words, particularly ones unrelated to scientific programming.
As far as the size of languages, that seems a matter of point of
view.  Python is a large language if you consider the standard
library to be part of the language, a very small one if you don't.
-John]

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Re: for or against equality, was Why are ambiguous grammars usually a bad idea? Martin Ward <martin@gkc.org.uk> - 2022-01-05 10:25 +0000
  Re: for or against equality, was Why are ambiguous grammars usually a bad idea? David Brown <david.brown@hesbynett.no> - 2022-01-06 09:11 +0100
    Re: what is defined, was for or against equality Thomas Koenig <tkoenig@netcologne.de> - 2022-01-06 16:43 +0000
      Re: what is defined, was for or against equality David Brown <david.brown@hesbynett.no> - 2022-01-07 12:06 +0100
      Re: what is defined, was for or against equality Spiros Bousbouras <spibou@gmail.com> - 2022-01-07 13:21 +0000
        Re: what is defined, was for or against equality Thomas Koenig <tkoenig@netcologne.de> - 2022-01-08 09:31 +0000
          Re: what is defined, was for or against equality Spiros Bousbouras <spibou@gmail.com> - 2022-01-08 22:28 +0000
            Re: what is defined, was for or against equality Thomas Koenig <tkoenig@netcologne.de> - 2022-01-09 00:09 +0000
              Re: what is defined, was for or against equality Spiros Bousbouras <spibou@gmail.com> - 2022-01-09 21:30 +0000
          Re: what is defined, was for or against equality David Brown <david.brown@hesbynett.no> - 2022-01-09 23:00 +0100
            Re: what is defined, was for or against equality Thomas Koenig <tkoenig@netcologne.de> - 2022-01-10 12:04 +0000
              Re: what is defined, was for or against equality David Brown <david.brown@hesbynett.no> - 2022-01-11 18:16 +0100
                Re: what is defined, was for or against equality Kaz Kylheku <480-992-1380@kylheku.com> - 2022-01-11 19:19 +0000
                Re: what is defined, was for or against equality gah4 <gah4@u.washington.edu> - 2022-01-11 14:18 -0800
                Re: what is defined, was for or against equality Thomas Koenig <tkoenig@netcologne.de> - 2022-01-12 19:02 +0000
                Re: what is defined, was for or against equality David Brown <david.brown@hesbynett.no> - 2022-01-13 08:24 +0100
                Re: what is defined, was for or against equality Thomas Koenig <tkoenig@netcologne.de> - 2022-01-13 11:17 +0000
          Re: what is defined, was for or against equality gah4 <gah4@u.washington.edu> - 2022-01-10 16:58 -0800
    Re: for or against equality, was Why are ambiguous grammars usually a bad idea? Robert Prins <robert@prino.org> - 2022-01-06 19:07 +0000
    Undefined behaviour, was: for or against equality Martin Ward <martin@gkc.org.uk> - 2022-01-07 14:02 +0000
      Re: Undefined behaviour, was: for or against equality Spiros Bousbouras <spibou@gmail.com> - 2022-01-08 03:41 +0000
    Re: Undefined behaviour, was: for or against equality David Brown <david.brown@hesbynett.no> - 2022-01-07 15:56 +0100
      Re: Undefined behaviour, was: for or against equality anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2022-01-08 17:52 +0000
        Re: Undefined behaviour, was: for or against equality David Brown <david.brown@hesbynett.no> - 2022-01-09 23:53 +0100
        Re: Undefined behaviour, was: for or against equality Kaz Kylheku <480-992-1380@kylheku.com> - 2022-01-11 16:55 +0000
          Re: Undefined behaviour, was: for or against equality George Neuner <gneuner2@comcast.net> - 2022-01-11 22:01 -0500

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