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

Michael Everson everson at
Thu Apr 16 13:46:47 CEST 2015

On 15 Apr 2015, at 17:57, Peter Constable <petercon at> wrote:

> If one wants to indicate dialectal variations (accent, lexicon, grammar), then (e.g.) "pt-PT" may be useful. 
> If one want to indicate a particular orthographic variation, they may choose to use "pt-PT", but that is not a reliable indicator of orthographic choices in general usage; it may be within a limited usage context (e.g. internal to some app or some managed corpus), but not in the general case. But "pt-ao1990" can be used as a reliable indicator of an orthographic variation in the general case — no region subtag required.
> Similarly, the variant subtag "pt-ao1990" is not going to be a reliable indicator of non-orthographic distinctions.

Right, and since the options it allows are dialectal in nature (aluminium vs aluminum) they are very likely going to be preferred one way or another by region, I continue to favour pt-BR, pt-CV, pt-PT as prefixes for this. It does not seem likely that pt-ao1990 could be useful to anyone.

> If one wants to indicate both dialectal and orthographic variations, then both region and variant subtags, e.g., "pt-PT-ao1990" may be useful.

Since that’s what the options are for, this seems self-evident to me.

Michael Everson *

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