However, all locales started using their calendars at some point and often we do support the calendar they've used before that point as well (i.e. Julian). For en, for example, it should be possible to use ICU4X to render something akin to the cal tool
$ cal 9 1752
September 1752
Su Mo Tu We Th Fr Sa
1 2 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
This uses the knowledge of when the en[^1] locale changed from the Julian calendar to the Gregorian calendar, which should be something ICU4X knows.
[^1]: Regions break down a bit if you go back that far, but incidentally every country that uses en today was part of the same country back then!
Currently we support resolving the correct calendar system for a locale. However, this is not data driven, but hardcoded: https://github.com/unicode-org/icu4x/blob/20c629a26c628a4e9e9915546b0d3a701a4789c0/components/calendar/src/any_calendar.rs#L1075-L1090
However, all locales started using their calendars at some point and often we do support the calendar they've used before that point as well (i.e. Julian). For
en, for example, it should be possible to use ICU4X to render something akin to thecaltoolThis uses the knowledge of when the
en[^1] locale changed from the Julian calendar to the Gregorian calendar, which should be something ICU4X knows.[^1]: Regions break down a bit if you go back that far, but incidentally every country that uses
entoday was part of the same country back then!