Discussion List Archives

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Backus-Naur Form for CIF

I think the BNF should be released with one more change.  The BNF as
currently posted at:


includes the statement:

"a CIF record (line of text) is restricted to 80 characters (from the set
defined in <char>). This character count doesn not include the record
termination character(s)."

As many of you know, various approaches to the relaxation of this limit are
being discussed.  I would be willing to vote in favor of the posted BNF,
_if_ the statement above were revised to read as follows:

"a CIF record (line of text) is restricted to 80 characters (from the set
defined in <char>). This character count does not include the record
termination character(s).  Various approaches to extending this limit are
under consideration.  Software developers are advised to make appropriate
allowances and to consider the present 80 character limit as subject to
change in the near future."

Naturally, whenever a firm decision is made on extending the limit, the BNF
should be revised to reflect whatever is decided, but it is only fair to
warn software developers right now that they cannot rely on the 80
character limit in designing parsers.

  -- Herbert

At 17:16 +0000 11/14/00, I. David Brown wrote:
>	It is now over a month since the last significant comment occurred
>in this discussion and I would invite the voting members of Comcifs to
>record their approval of the Backus-Naur Form for CIF that Nick Spadaccini
>has prepared.  The correspondence can be viewed on the IUCr web site.
>	At least one member has already recorded his approval on this
>discussion group and I now indicate my approval.  Please record your vote
>either on the discussion group or to Brian McMahon with a copy to me.
>			David
>Dr.I.David Brown,  Professor Emeritus
>Brockhouse Institute for Materials Research,
>McMaster University, Hamilton, Ontario, Canada
>Tel: 1-(905)-525-9140 ext 24710
>Fax: 1-(905)-521-2773

****                BERNSTEIN + SONS
****     P.O. BOX 177, BELLPORT, NY 11713-0177
*   * ***
**** *            Herbert J. Bernstein
  *   ***     yaya@bernstein-plus-sons.com
 ***     *
  *   *** 1-631-286-1339    FAX: 1-631-286-1999