Thanks for tips to external Date/Time implementation. I implemented custom #= and #< methods in Date class as extension to solve my issue.
It's sad a little, that base Date/Time classes is not enough and external libs existed. pf > > > On 26 Mar 2017, at 21:56, Stephane Ducasse <stepharo.s...@gmail.com> wrote: > > > > Did you check the Zn counterpart because I know that some parts are much > > better. > > But I do not have them at hand. > > You mean ZTimestamp (but it is not a part of Zinc HTTP Components). > > https://github.com/svenvc/ztimestamp > > This is an UTC, second precision timestamp without TZ info, and a number of > interesting tools. > > However, that won't solve the issue raised. Some people think of a date as an > abstract calendar date, while for others its a concrete day (my Monday is not > your Monday if we are in different time zones). > > I don't think there is only one solution, both roles are needed/useful. > > Note that STON serialises Dates as YYYY-MM-DD which is what you seem to want. > > The ZTimezone class knows about the exact transitions, but that still does > not mean that no weird things happen at the transition point, au contraire ;-) > > > Stef > > > > On Sun, Mar 26, 2017 at 10:17 AM, Petr Fischer <petr.fisc...@me.com> wrote: > > Hello, > > > > 1) when I create date on: 2017/03/20 (before Daylight Saving Time change) > > with this code: > > > > D1 := Date year: 2017 month: 3 day: 26. > > > > Date object is created with instvars: > > start: 2017-03-26T00:00:00+01:00 > > duration: 1:00:00:00 > > > > 2) when I create same Date instance with the same code on/after: 2017/03/26 > > (after Daylight Saving Time change): > > > > D2 := Date year: 2017 month: 3 day: 26. > > > > Date instance with this instvars returned: > > start: 2017-03-26T00:00:00+02:00 > > duration: 1:00:00:00 > > > > 3) D1 != D2 > > > > So, for example: persisted instance of date (Date year: 2017 month: 3 day: > > 26) created before DST change is not equal with date instance (Date year: > > 2017 month: 3 day: 26) created after DST change. > > DST change breaks equality of the same date :( > > > > Is it OK? > > > > Thanks! Petr Fischer > > > > > >
