Region subtags and orthographic variants (was: Re: registration requests re Portuguese)

Doug Ewell doug at
Thu Apr 16 19:23:31 CEST 2015

Yury <yury dot tarasievich at gmail dot com> wrote:

> After Mark's post, I re-browsed the RFC beyond the ABNF and section 3.
> Rule can be understood as either (1) "the order of use of
> 'language' and 'region' must be 'language', then 'region'" or (2)
> "there must always be 'region' after 'language'". First is completely
> redundant (by ABNF) and not corroborating Mark's post, so second must
> be it -- Mark claims so, and he is the rfc5646 author, after all. But
> then it overrides the rfc5646 ABNF with region being optional (square
> brackets rule, rfc5234#3.8).

Region subtags are always optional.

For "Region subtags MUST follow..." you should read "The region subtag,
if present, MUST follow..."

Doug Ewell | | Thornton, CO 🇺🇸

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