Re: [Json] ABNF nits -- LAST CHANCE ON PROPOSALS

Carsten Bormann <cabo@tzi.org> Wed, 12 June 2013 18:16 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Wed, 12 Jun 2013 20:16:36 +0200
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Subject: Re: [Json] ABNF nits -- LAST CHANCE ON PROPOSALS
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On Jun 12, 2013, at 17:19, Stefan Drees <stefan@drees.name> wrote:

> Wouldn't it be better

Well, I apologize for making editorial comments on the ABNF.  
We have more important things to decide right now; I was incited by the "LAST CHANCE" message.

The single-level grammars created by RFC 5234 ABNF are generally a lot better for describing protocols than the scanner/parser grammar pairs used by programming language standards (like ECMAscript).  ABNF tends to be a bit verbose around the optional whitespace, but I think Douglas has hit this nail on the head with the single exception that he maybe should have called ws ows (optional white space).
For the reasons I gave, changing this is only worth it if we are changing a lot of the rest.

Norbert's observation of course is spot on; I must admit I didn't read the comments at all.
(Maybe we can avoid writing the somewhat disconnected U+YYYYYY, though, and instead point to the fourth paragraph of 2.5, "U+XXXX or part of a surrogate pair, see Section 2.5".)

Grüße, Carsten