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

Re: On ABNF in 5322: Advice needed




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
places.


-- 
Bill McQuillan <McQuilWP@xxxxxxxxx>