On 13.1.2013 14:52, TAMURA, Kent wrote:
On Tue, Jan 8, 2013 at 9:47 AM, Ian Hickson <i...@hixie.ch> wrote:
> However, I'm not sure how this can be presented to the user. In the
> example above I suggested that time input UI should be accompanied
with
> local time zone ("Europe/Helsinki" in my example). However, that would
> suggest that this info would be transferred to the server and that the
> server is expected to follow political time zone changes to that
> timezone. The user could be assuming that he has defined a specific
time
> in a specific timezone (an absolute time as far has he knows).
>
> In the reality, the server would like to transfer *the responsibility*
> for the possible future time zone changes to the user -- the server
> expects user to come by and modify the absolute time in case the user
> local timezone has been modified since entering this absolute time. I
> have absolutely no idea how on earth this could be explained to casual
> user. And even if it could be explained, I'm pretty sure the end user
> wouldn't be happy with that responsibility.
Yeah. Indeed.
> The next best choice would be to have datetime-with-timezone but
> unfortunately
>
> (1) Official database for all timezones does not exist
> (2) Official timezone names (or labels) do not exist
> (3) Timezones are subject to future political decisions
>
> The problems (1) and (2) make transferring the timezone information
from
> the end user to the server very problematic and the problem (3) makes
> any work to fix (1) and (2) a bit pointless. This is because even
if UA
> could successfully inform the server about the correct timezone, the
> server could be using a week old timezone data that is not up to the
> latest political events. Or the server might be using latest timezone
> data but the UA could be using three year old data. In either case,
the
> absolute time in UTC could be different for the server and UA.
Indeed.
So, I think it's impossible for us to build reasonable UI for
type=datetime. It should be removed from the specification.
--
TAMURA Kent
Software Engineer, Google
datetime-local shoud be removed from specification and datetime should
reflect user's settings (e.g. underlying OS)
BK
