ISO standard for EBNF 
Author Message
 ISO standard for EBNF

Just in case anyone is interested, ISO has finally standardized
the Extended Backus-Naur Form for context free grammars:

  ISO/IEC 14977:1996 Information technology -- Syntactic
  metalanguage -- Extended BNF

Markus

--
Markus G. Kuhn, Security Group, Computer Lab, Cambridge University, UK
email: mkuhn at acm.org,  home page: < http://www.*-*-*.com/ ~mgk25/>



Fri, 02 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

>Just in case anyone is interested, ISO has finally standardized
>the Extended Backus-Naur Form for context free grammars:

>  ISO/IEC 14977:1996 Information technology -- Syntactic
>  metalanguage -- Extended BNF

>Markus

Visio template at 11, right?

                             -dlj.



Fri, 02 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

> >Just in case anyone is interested, ISO has finally standardized
> >the Extended Backus-Naur Form for context free grammars:

> >  ISO/IEC 14977:1996 Information technology -- Syntactic
> >  metalanguage -- Extended BNF

I thought they did that in 1981 (Oh, checking again I see that was a BS
- BS6154 of 1981)

So what has been added?  I always thought Wirth got it right in
COmm ACM 20(11), 822-823 (1977).  The BS one added a whole lot of noise.

Mind you, ISO added a lot of noise to Modula-2 as well.  Seems we can
never avoid it!

--

Rhodes University, Grahamstown, South Africa
+27-46-603-8292 (voice) +27-46-636-1195 (FAX)



Fri, 02 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:
>Just in case anyone is interested, ISO has finally standardized
>the Extended Backus-Naur Form for context free grammars:
>  ISO/IEC 14977:1996 Information technology -- Syntactic
>  metalanguage -- Extended BNF

Is there a URL for it?

--
Charles H. Lindsey ---------At Home, doing my own thing------------------------

Voice/Fax: +44 161 437 4506      Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K.
PGP: 2C15F1A9     Fingerprint: 73 6D C2 51 93 A0 01 E7  65 E8 64 7E 14 A4 AB A5



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

>>  ISO/IEC 14977:1996 Information technology -- Syntactic
>>  metalanguage -- Extended BNF

>Is there a URL for it?

The view by the ISO is that only those that can afford buying their
standards should use them; their standards are not made publically
available the way information intended for public use is (such as
government and scientific data). It is not possible to make an ISO
standard publically available on a URL even if those that did the job,
creating the standard, want that to be done.

So, in particular, if somebody try to force you to use a particular ISO
standard, just mention that you are not interested in investing the money
in that particular commercial product.

  Hans Aberg   * Anti-spam: Remove "REMOVE." from email address.

               * Home Page: <http://www.matematik.su.se/~haberg/>
               * AMS member listing: <http://www.ams.org/cml/>



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:


> >Just in case anyone is interested, ISO has finally standardized
> >the Extended Backus-Naur Form for context free grammars:

> >  ISO/IEC 14977:1996 Information technology -- Syntactic
> >  metalanguage -- Extended BNF

> Is there a URL for it?

I will write a summary/tutorial of the standard (like the other
summaries of ISO standards on my home page), which will be on

  http://www.cl.cam.ac.uk/~mgk25/iso-ebnf.html

Markus

--
Markus G. Kuhn, Security Group, Computer Lab, Cambridge University, UK
email: mkuhn at acm.org,  home page: <http://www.cl.cam.ac.uk/~mgk25/>



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF



|> >>  ISO/IEC 14977:1996 Information technology -- Syntactic
|> >>  metalanguage -- Extended BNF
|> >
|> >Is there a URL for it?
|>
|> The view by the ISO is that only those that can afford buying their
|> standards should use them; their standards are not made publically
|> available the way information intended for public use is (such as
|> government and scientific data). It is not possible to make an ISO
|> standard publically available on a URL even if those that did the job,
|> creating the standard, want that to be done.

This is nonsense.  The reason that they charge so much is that they
are constrained to be self-supporting, and the only thing that can
sell IS their standards.  Yes, it is undesirable, but it is neither
the fault of ISO nor what most of ISO would like.  There are certainly
some petty (and even stupid) bureaucrats in ISO, who don't realise
that the high prices are counter-productive, but that is not the
issue.

Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QG, England.

Tel.:  +44 1223 334761    Fax:  +44 1223 334679



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

> > >  ISO/IEC 14977:1996 Information technology -- Syntactic
> > >  metalanguage -- Extended BNF

> So what has been added?  I always thought Wirth got it right in
> COmm ACM 20(11), 822-823 (1977).  The BS one added a whole lot of
> noise.

I don't know BS6154, but I can quickly summarize the differences
between ISO 14977 and Wirth's paper:

The ISO EBNF is almost a superset of Wirth's, with the following
exceptions:

 - productions are terminated with a ; and not a .
 - both single and double quotes are allowed, with the other
   type of quote allowed inside the terminal symbol (not
   using Wirth's double-double-quote rule

The main extentions are:

 - the comma is the concatenation operator
 - a '*' is a multiplication operator, i.e. "a"*5 = "aaaaa", and
   ["a"]*5 = "" | "a" | "aa" | ... | "aaaaa".
 - a '-' allows to subtract a regular language from a
   context free language
 - (* and *) delimit comments

I think it is a quite handy extention of Wirth's EBNF, especially
the multiplicator allows you to specify maximum lengths of strings
conveniently. I am just a bit concerned that the '-' operator is
much more difficult to implement than the rest, so I would use it with
care only.

Markus

--
Markus G. Kuhn, Security Group, Computer Lab, Cambridge University, UK
email: mkuhn at acm.org,  home page: <http://www.cl.cam.ac.uk/~mgk25/>



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

>This is nonsense.  The reason that they charge so much is that they
>are constrained to be self-supporting, and the only thing that can
>sell IS their standards.  Yes, it is undesirable, but it is neither
>the fault of ISO nor what most of ISO would like.  There are certainly
>some petty (and even stupid) bureaucrats in ISO, who don't realise
>that the high prices are counter-productive, but that is not the
>issue.

The problem is that the high prices make perfectly good sense for standards
where it's sufficient for one person in a large firm to have a copy (many
of the architectural standards are like this), but are flat out stupid for
standards where it's best for everyone to have a copy (like C9X, plug plug.)

-s
--

C/Unix wizard, Pro-commerce radical, Spam fighter.  Boycott Spamazon!
Seeking interesting programming projects.  Not interested in commuting.
Visit my new ISP <URL:http://www.plethora.net/> --- More Net, Less Spam!



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

>This is nonsense.  The reason that they charge so much is that they
>are constrained to be self-supporting, and the only thing that can
>sell IS their standards.  Yes, it is undesirable, but it is neither
>the fault of ISO nor what most of ISO would like.  There are certainly
>some petty (and even stupid) bureaucrats in ISO, who don't realise
>that the high prices are counter-productive, but that is not the
>issue.

  Well, I wanted to point out how absurd and counter-productive those high
charges are, so it seems that I did pretty well.

  Hans Aberg   * Anti-spam: Remove "REMOVE." from email address.

               * Home Page: <http://www.matematik.su.se/~haberg/>
               * AMS member listing: <http://www.ams.org/cml/>



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

>The problem is that the high prices make perfectly good sense for standards
>where it's sufficient for one person in a large firm to have a copy (many
>of the architectural standards are like this), but are flat out stupid for
>standards where it's best for everyone to have a copy (like C9X, plug plug.)

  Exactly, the whole idea of ISO is outdated in this respect, in view of
that maximum spread of a standard can be done via WWW these days, and this
is needed in order to get the proper feed-back for developing those
standards.

  Hans Aberg   * Anti-spam: Remove "REMOVE." from email address.

               * Home Page: <http://www.matematik.su.se/~haberg/>
               * AMS member listing: <http://www.ams.org/cml/>



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF

Quote:

> The problem is that the high prices make perfectly good sense for standards
> where it's sufficient for one person in a large firm to have a copy (many
> of the architectural standards are like this), but are flat out stupid for
> standards where it's best for everyone to have a copy (like C9X, plug plug.)

It is true that certain standards (for example all programming
language standards, and other frequently required reference
material) should absolutely be available from normal bookshops
under conditions comparable to school textbooks, as well as
freely online.

This is certainly not impossible: The Ada 95 standard is available
at a moderate price from Springer in the Lecture Notes on Computer
Science series in every bookshop (and so is the rational):

  S. Tucker Taft et al.: Ada 95 Reference Manual - Language and
  Standard Libraries. International Standard, ISO/IEC 8652:1995(E),
  Springer, LNCS 1246, ISBN 3-540-63144-5, USD 54.95

It is also available online in various formats, e.g. on

  http://wuarchive.wustl.edu/languages/ada/

It would be an excellent idea if the ISO C and C++ committees could get
a similar arrangement with ISO on the availability of the standard
as the ISO Ada committee did. The participation of government
employees in drafting the standard is usually the legal leverage
that leads to success, because the result of government funded
work is not copyright protectable in many countries (after all, it
is your tax money that paid the project).

The Ada95 ISO standard is usually available on the desk of every
Ada hacker, because it is public domain and you usually get one
delivered with every commercial compiler as part of the manual.
It is even quite common practice that Ada compiler error messages
quote the section in the standard that your code violated, and
Ada programmers are usually quite aware of the details of the standard,
which is certainly not the case for most C/C++ programmers, mostly
because their language standard is very expensive and not available
online.

Markus

--
Markus G. Kuhn, Security Group, Computer Lab, Cambridge University, UK
email: mkuhn at acm.org,  home page: <http://www.cl.cam.ac.uk/~mgk25/>



Sat, 03 Mar 2001 03:00:00 GMT  
 ISO standard for EBNF


[ ... ]

Quote:
> The view by the ISO is that only those that can afford buying their
> standards should use them; their standards are not made publically
> available the way information intended for public use is (such as
> government and scientific data). It is not possible to make an ISO
> standard publically available on a URL even if those that did the job,
> creating the standard, want that to be done.

More accurately, the view from the ISO is that it costs money for the
ISO to exist and create standards, and the cost should be absorbed by
those use use the standards, particularly since they haven't got much
other source of income.  However, when arrangements are made up-front
to allow it, some ISO standards have been made freely available; the
ISO standard for Ada is one obvious example.

--
    Later,
    Jerry.

The Universe is a figment of its own imagination.



Sat, 03 Mar 2001 03:00:00 GMT  
 
 [ 30 post ]  Go to page: [1] [2] [3]

 Relevant Pages 

1. ISO standard for EBNF

2. question: iso 14977 ebnf grammar for Python?

3. branching in proposed ISO standard

4. ISO Standards Documents

5. ISO International Standard IS8485

6. ISO Standard for Headless Images?

7. ISO Standard Forth

8. ISO Standard for Software Revisions

9. ISO Standard Approved

10. Oberon ISO-Standard?

11. Static scoping in BCPL (was Re: Are nested functions legal in ANSI/ISO Standard C)

12. Cost of ISO Standard Documents

 

 
Powered by phpBB® Forum Software