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Re: On ABNF in 5322: Advice needed

2008-09-26 05:04:01

On Thu, 2008-09-25, Pete Resnick wrote:

5322 (nee 2822upd) is in AUTH48. During this process, the editor 
noted some confusion about some of the text: Sometimes when I say 
(e.g.) "phrase", it's not clear whether I'm referring to the ABNF 
terminal "phrase" or a description of it. It's somewhat easy to 
distinguish, for instance, "a quoted string" from "quoted-string", 
but other places it's trickier.

Quoting from RFC 5234, "Augmented BNF for Syntax Specifications", 2.1:

   Unlike original BNF, angle brackets ("<", ">") are not required.
   However, angle brackets may be used around a rule name whenever their
   presence facilitates in discerning the use of a rule name.  This is
   typically restricted to rule name references in free-form prose[...]

This seems to me to allow angle brackets to be used in only those places
where it is needed to remove ambiguity.

If I understand you correctly, you have already found a small number of
places where ambiguity exists, so I would recommend changing just those

Bill McQuillan <McQuilWP(_at_)pobox(_dot_)com>