Re: [Tzdist] Fwd: [tzdist] #32 (service): managing historical data

[Eliot Lear <[e-mail]>]

On 12/11/14, 7:28 PM, Lester Caine wrote:

> Calendaring systems still do not cover cross timezone activities well,
> and I don't think iCalendar is particularly friendly in solving the
> problems that need to be handled

There are some limitations that are inherent, when dealing with
timezones, but they are relatively few (like handling recurring meetings
during transitions).  None of that is relevant here.  Complaints about
vendor products are best dealt with in the market place and not in the
working group, unless there is a specific relevant interoperability
concern that impacts the protocol we are developing.

> For genealogical data we often flag a
> time range covering the uncertainty in when an event happened so that
> when time lining events one can see if something could have been
> concurrent which can then can be researched in further detail. While
> planning new events where a site may have a variation of local offset it
> would be useful that the tzdist data actually flagged that there is
> uncertainty in a forthcoming event if only to allow an organiser to
> block bookings on that day or period.

Variations in local offset are not always predictable.  Moreover, there
is an interaction with recurring events that would make such a feature
virtually impossible to get right.

Eliot