Re: [Ietf-languages] Suggestion to update Urdu Script Designation in the subtag registry

[Richard Wordingham <[e-mail]>]

On Thu, 13 Aug 2020 14:49:27 +0200
Hugh Paterson III <[e-mail]> wrote:

> ri,
> 
> In Nigeria Hausa can also be written with the Latin script. Where can
> I go to find what the basic default assumptions are for a language
> tag? Is the default always Latin?

Unless there is a suppress-script tag for the language, the default is
not normatively defined.  The ICU database, CLDR, seems to have
empirical fallback rules, but they're not trustworthy.  They have
(have had?) such howlers as the Saurashtra script being the default for
the Saurashtra language.  (The proposal for the script's encoding
noted that speakers usually used a different script for their
language.  I have reported the howler.)  It's a lot of work to dig this
information out, and sane fallback might even depend on the context, as
I've noticed in the choice of digits for page numbering in Thai -
magazines use (Western) Arabic digits, while the government sponsored
dictionary uses Thai digits. The Northern Thai nameplates in a Chiang
Mai university will use the Tai Tham script, but if you're trying to
spread the word of God, you'll use the Thai script with Bangkok spelling
rules.  The recent New Testament translation into Northern Thai used
both scripts because of the competing requirements. (The two NT versions
correspond very exactly.) Most Northern Thai speakers can function in
Thai.

Richard.