[FR] Allow BC years in timestamps (was: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda)

[Ihor Radchenko <yantar92@posteo.net>]

Tom Gillespie <tgbugs@gmail.com> writes:

>> > As for years BC, <-0001-...> will be a breaking change. But I do not
>> > think that we need to really worry about this. Not unless we actually
>> > get feature request. What is the practical application?
>
> Using org as a format for writing about history and being able to
> reference dates in the past accurately and have the dates be
> first class entities that can be parsed and checked etc.
>
> The example in my head is a history professor who wants to
> write about e.g. the collapse of the Roman republic and not
> have to come up with their own time keeping system or force
> any one who wants to work with referenced dates to do a bunch
> of math to translate from a roman time system to a modern one.

This is an OK feature request. But it is orthogonal to time zones. Time
zones cannot help with BC years.

To support BC, we may need to change the timestamp format to, for
example, allow negative years. In addition, we might need to update
exporters to handle such scenarios.

Let's discuss BC/AC years in this thread, if there is further interest.

-- 
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
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