Language codes

Lang Gérard gerard.lang at
Fri Sep 11 17:17:00 CEST 2009

UK is one of the ten "exceptionally reserved" alpha-2 code elements inside ISO 3166-1.
This reservation has been asked by BSI, and accepted by ISO 3166/MA, the reason being that in the initial cctld IANA  register that should have contained ".gb", due to a personal error of John Postel, "uk" was registered.
So I have no problem if the alpha-2 code elements FX andUK were added, and the clause 2.4 New Region Subtags  of RFC 5645 accordingly modified concerning FX and UK.
By the way, following the insertion of SU inside the list (ISO 3166/MA N 563  2008-06-27), there are currently ten exceptionally reserved alpha-2 code elements, and not nine as written on line six inside clause 2.4 of RFC 5645.
Bien cordialement.
Gérard LANG

-----Message d'origine-----
De : ietf-languages-bounces at [mailto:ietf-languages-bounces at] De la part de Doug Ewell
Envoyé : mardi 8 septembre 2009 04:20
À : ietf-languages at
Objet : Re: Language codes

Mark Davis ⌛ wrote:

> What we do is act like "UK" was in the registry, but deprecated in 
> favor of "GB", since that solves the problem.

By "we" I assume you mean Google.  Certainly, any implementer of a matching engine can add their own private extension such as this.

> (What would have been a good general solution.)

No, it wouldn't.  Are we going to carry over this battle from LTRU? 
Adding a pre-deprecated, *wrong* subtag to document and legitimize some users' *wrong* usage would not have been a good general solution.

RFC 5646 points out (correctly) that deprecated subtags are "valid in language tags" and can even be "preferred in certain contexts."  This would have sent the wrong message entirely in the case of 'GB' vs. 'UK'. 
The place for users to find valid BCP 47 subtags is in the Registry, not at the end of e-mail and Web addresses, not on the white elliptical decals on the rear bumpers of cars, not in the abbreviate forms that people use in speech.

Doug Ewell  |  Thornton, Colorado, USA  | RFC 5645, 4645, UTN #14  |  ietf-languages @

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