The transformed content language tag extension [RFC6497], which uses the
-t-subtag, provides subtags for text transformations, such as transliteration between scripts. See Section 3.7 of [LDML] for details.
Language Tags and Locale Identifiers for the World Wide Web https://www.w3.org/TR/ltli/#ref-for-dfn-language-tag-extension-3
@nixeneko
BCP 47 の T Extension で表現できるっぽい
Unicode Locale Data Markup Language (LDML)
https://www.unicode.org/reports/tr35/tr35.html#t_Extension
ref: https://pl.kpherox.dev/notice/AWHnojnntm7zEBlZwm
`mn-Cyrl-t-Latn` でキリル文字モンゴル語のラテン文字翻字、`mn-Mong-t-Latn` でモンゴル文字モンゴル語のラテン文字翻字になるかも
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Type: variant
Subtag: alalc97
Description: ALA-LC Romanization, 1997 edition
Added: 2009-12-09
Comments: Romanizations recommended by the American Library Association
and the Library of Congress, in "ALA-LC Romanization Tables:
Transliteration Schemes for Non-Roman Scripts" (1997), ISBN
978-0-8444-0940-5.
%%
%%
Type: script
Subtag: Mong
Description: Mongolian
Added: 2005-10-16
%%
%%
Type: script
Subtag: Cyrl
Description: Cyrillic
Added: 2005-10-16
%%
%%
Type: redundant
Tag: mn-Cyrl
Description: Mongolian in Cyrillic script
Added: 2005-02-17
%%
Type: redundant
Tag: mn-Mong
Description: Mongolian in Mongolian script
Added: 2005-02-17
%%
そーいや、ロケールだか言語タグだかで言語のスクリプト指定できる仕組みあったけど、「モンゴル語モンゴル文字表記のラテン文字転写」と「モンゴル語キリル文字表記のラテン文字転写」を区別することってできるのかな