[threeten-dev] Islamic calendar variants need disambiguation

[Dan Chiba]

Yoshito-san,

I would like to get your opinion about identifying Islamic calendar 
variants in CLDR. It defines "islamic" and "islamicc" in calendar.xml 
for the astronomical and algorithmic variants respectively, while 
JSR-310 needs to clearly identify the variants and distinctively 
identify each of them, in order to identify the dates correctly.

For example, the Umm Al-Qura calendar and Microsoft's Islamic calendar 
implementation with the Kuwaiti algorithm are both algorithmic but they 
are different, so the date information is not interchangeable under 
"islamicc" between different variants. A date in one variant may 
correspond to a different date in another variant. So, in terms of 
ensuring correct exchange of Islamic date information, not identifying 
the precise variants in the CLDR name space falls short of the use case 
expectation. In JSR-310, we anticipate Islamic end users might have 
their preferred Islamic calendar variant set in their user profile, or 
an application may be supporting different variants in producing some 
output with Islamic date information.

May I ask if there is a chance to add more Islamic calendar variants or 
enhance the calendar naming scheme to resolve this issue? Or is this 
beyond the scope of CLDR? Do you suggest taking this to the CLDR list?

Regards,
-Dan