How many subtags is ideal? [RE: LANGUAGE TAG REGISTRATION FORM: iu-Cans]

John Cowan jcowan at
Sat Feb 5 05:56:25 CET 2005

John Clews scripsit:

> Should they be used only exceptionally? In many cases, for most users (and
> developers?) 2 element tags (language-script) will be sufficient, and the
> third element will not add much differentiation, but the fact that
> 2-element and 3-element tags may cause some interoperability problems.

I agree completely, and I think that's the general opinion on the list
as well.

> On the other hand, I even the 3-element tag may not be enough. Indeed, I
> understand that there are different spelling conentions used in writing
> Inuktitut in syllabics in Eastern and Western parts of Canada.

It is possible to register more complex tags when and as needed.

> That could be solved by using 4-element codes, with the 4th element coming
> from subtags from ISO 3166-2 (or elsewhere).

We currently have a self-imposed restraint that all subtags for language
variants (dialectal or orthographic) be 5 or more letters, or 4 or more
digits, long.  So en-US-Texas would be a plausible tag.

> Or in the medium term (and better still?) that same situation may be
> solved once it becomes decided that it is possible to use codes from the
> forthcoming ISO 639-3, where the differentiation would almost certainly be
> achieved by using a different 3-letter language subtag as the first subtag
> in the cases of:
> East Canadian Inuktitut written in Syllabics, and
> West Canadian Inuktitut written in Syllabics.

Indeed.  Currently, ISO 639-3 tags cannot be used in the first subtag,
but they can be used in later ones; iu-ike (Eastern) and iu-ikt (Western)
are plausible tags, as are related tags ending in -Cans or -Latn.

                Si hoc legere scis, nimium eruditionis habes.

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