[Development] QTimeScheme for Qt - 5.0 or 5.1?

[Konrad Rosenbaum]

Hi,

On Wednesday 01 February 2012 01:59:49 Stephen Kelly wrote:
> On Tuesday, January 31, 2012 22:50:51 you wrote:
> > * I'd prefer if we don't have to ship the database. As noted it can
> > change easily
> > and a compiled in database would get out of sync.

Look for the system database - on systems that are based on Olson DB it's 
always on very few specific locations. For the others ship a backup resource 
file or plugin.

> > * ICU has timezone support as well. Something that could simplify our
> > life?
> 
> Wouldn't that be out of sync too? What is the ICU timezone support?

ICU ships a copy of the Olson DB.

> > * Do we need to support both the Windows and Unix format, or could we get
> > away with Unix only in a first version (if e.g. ICU provides the data)?
> 
> I think this is 5.x material anyway. I think it would need somewhat more
> involved discussion.

Windows names can be mapped to Olson names - there are lists on the web. The 
calculation results are almost identical. Almost.

A parser for Olson DB files is not overly complex to write - I did that within 
a weekend.

git://silmor.de/konrad/tzone.git

I haven't completely checked Stephen's interface, but I had the distinct 
feeling that it underestimates the complexity of time zones:
*the definition of standard time and/or DST can change for any time zone at any 
time
*there can be 1 or up to 3 different time specs in a year (under exceptional 
circumstances even more)
*it is not always clear which time spec is standard and which one is DST




	Konrad
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part.
URL: <http://lists.qt-project.org/pipermail/development/attachments/20120215/2bb9557d/attachment.sig>