Re: [Ltru] Re: Remove extlang from ABNF?

I like that approach; clever.

On Dec 12, 2007 8:22 AM, Addison Phillips <addison@yahoo-inc.com> wrote:

> Felix Sasaki wrote:
> >>
> >> In RFC 4646, we defined some tags as well-formed. In RFC 4646bis, we
> >> suddenly
> >> say that some of these tags are not well-formed. We never would do
> >> this for
> >> valid tags, so I'm really not sure it is a good thing to do for
> >> well-formed tags.
> >>
> > +1
> >
>
> I agree.... except....
>
> This is exactly what we did in RFC 4646. We made a vast array of
> "well-formed" but invalid tags illegal (by narrowing the ABNF). In
> 4646bis, one could say that we were doing the same thing--making a (much
> smaller) array of tags (which were never valid) illegal. And we *have*
> changed the ABNF in a manner that narrows it in 4646bis already. We have
> narrowed the grandfathered production substantially.
>
> I have no problem with XML Schema or others referencing the 4646 ANBF
> instead of the 4646bis ABNF for well-formness checking. It won't
> introduce anything particularly bad. And I am somewhat allergic to
> changing the ABNF because I have personally felt like we should resist
> tampering.
>
> As an implementer, though, I really hate supporting extlang, now that it
> does nothing. So I'd propose:
>
> 1. Remove extlang from the ABNF in 4646bis. That would make the language
> production:
>
> language      = (2*3ALPHA)             ; shortest ISO 639 code
>               / 4ALPHA                 ; reserved for future use
>               / 5*8ALPHA               ; registered language subtag
>
>
> 2. In the section on conformance, permit 4646bis well-formedness to
> reference either the current ABNF or an "obs-language" production that
> looks like:
>
> obs-language  = (2*3ALPHA [ extlang ]) ; shortest ISO 639 code
>               / 4ALPHA                 ; reserved for future use
>               / 5*8ALPHA               ; registered language subtag
>
> extlang       = *3("-" 3ALPHA)         ; removed in this version
>
> 3. Add a note saying that no tags were ever valid under obs-language,
> but that some processors may permit them. Also note that 3066
> well-formedness differed substantially from 4646/4646bis well-formedness
> and provide the 3066 production in that section for completeness.
>
> Addison
>
> --
> Addison Phillips
> Globalization Architect -- Yahoo! Inc.
> Chair -- W3C Internationalization Core WG
>
> Internationalization is an architecture.
> It is not a feature.
>
>
> _______________________________________________
> Ltru mailing list
> Ltru@ietf.org
> https://www1.ietf.org/mailman/listinfo/ltru
>

-- 
Mark