Mark Davis ☕️ mark at
Tue Jan 3 08:15:55 CET 2017

-u- is syntacticly unsuitable, as well as being a worse fit semantically.
You can use es-t-en-c0 or es-t-en-gb-c0. You can't use es-u-en-c0, or
es-u-en-gb-c0 because any two letter subtag is a reserved keyword.

I was not arguing in favor of using -u- extension for code-switch
languages, just saying that it /is/ a broad mechanism.


On Mon, Jan 2, 2017 at 7:10 PM, Phillips, Addison <addison at>

> >
> > > The much
> > > more general mechanism is the U one, which by now has a variety of
> > > different settings.
> >
> > Ah, yes, forgot about that. I think it would be much better then to use
> the U
> > extension.
> >
> The U extension is for Locale information. I don't think that fits any
> better. If anything, it's a worse fit.
> Addison
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