Re: [Json] [Technical Errata Reported] RFC8259 (7650)

[Carsten Bormann <[e-mail]>]

On 2023-09-20, at 17:46, Lucas TESSON <[e-mail]> wrote:
> 
> It has been widely accepted that ABNF Core rules always lie in the grammar, leading to this errata.

As Julian mentioned, implicit importing is not that widely accepted.

> Note that the BAP tool used by the IETF to validate ABNF grammar don't raise an error on this, which may be an actual issue in its implementation.

ABNF in reality is almost as much defined by BAP as by RFC 5234.
Generations of spec writers have used BAP to check their ABNF.

Of course, you can extract the ABNF from RFC 5234 B.1, put it into core-rules.abnf, and do a

   aex rfc8259.txt | bap -i core-rules.abnf

to see the problem (*), but who knows that?

My point is that if using the core rules requires explicit action in the most widely used ABNF tool, implicit importing can’t be that wide-spread.

Grüße, Carsten

(*)
stdin(53:29): warning: rule CHAR defined on line 4 referred to as char
stdin(66:0): error: Rule char previously defined as CHAR on line 4
stdin(66:0): error: Rule char was already defined on line 4 of core-rules.abnf