Re: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda

[Ihor Radchenko]

Jean Louis <bugs@gnu.support> writes:

> ...
> Should be part of C library to observe those things.

Sure. My previous proposals are all relying on `encode-time' which uses
time.h from system libraries and utilizing TZDB that is taking care
about all this insanity.

We, however, might need to be careful about applying date increments. In
`org-read-date' and `org-timestamp-change', which are implemented in
Elisp without considering these complexities. (maybe also other
functions; these are just the ones I can think about)

What should we do when:

1. It is close to DST transition 2:59 -> 2:00 -> 2:01 -> ... -> 2:59 -> 3:00
   and the users asks to create a timestamp +1h from now
   or, worse, a timestamp +1h from now in a different time zone

2. A user asks +1w date shift and the time zone has a 1-day jump during DST?
   what about +7d? +1d?

3. What will be +1d 2:30am timestamp refer to when there DST transition
   as in (1)?


-- 
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
Support Org development at <https://liberapay.com/org-mode>,
or support my work at <https://liberapay.com/yantar92>