<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On 7 July 2014 18:44, Jon Skeet <span dir="ltr"><<a href="mailto:skeet@pobox.com" target="_blank">skeet@pobox.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
I think at the moment I always assume that the time of day and the date are in the same frame of reference - so in the above example, I suspect I'd find a transition at Monday April 1st, 2am UTC</blockquote></div><br>
This, too, is my personal understanding of at least the <i>intent</i> behind the
interpretation of years, months, and dates in FROM, TO, TYPE, IN, and
ON, That is, they are to take the same interpretation as the suffix which applies to AT.<br><br>In your example: Since 2:00u is
specified for the transition, Apr Mon>=1 should be treated as
Universal time, then find 02:00Z within that day. So transition Monday 1
April 02:00 UTC, which is Sunday 31 March 18:00 UTC–8.<br><br><div class="gmail_quote">On 7 July 2014 17:57, Paul Eggert <span dir="ltr"><<a href="mailto:eggert@cs.ucla.edu" target="_blank">eggert@cs.ucla.edu</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Transitions are given in terms of the local time before the transition, as otherwise a transition could be self-referential.</blockquote>
</div><br></div><div class="gmail_extra">This doesn't seem it should apply to transition rules with "u"/"g"/"z" suffix; only those with "s" or "w"/no suffix.<br></div>
<div class="gmail_extra"><br></div><div class="gmail_extra">"Standard time" rules would be computed similarly to "Universal time" rules. Find the span of the specified date in the zone's standard time (as reckoned by the offset PRIOR to the transition), then find the specified standard time within that span.<br>
<br></div><div class="gmail_extra">"Wall clock time" rules with no suffix (or a "w" suffix) would find the span of the date in the zone's wall clock time (as reckoned by the PRIOR offset), then find the proper wall clock time.<br>
<br></div><div class="gmail_extra">I think this seems the most logical for maintenance and rule-writing, as any rule specified in, e.g., UTC, ought to recur in UTC.<br><br>For a concrete example, see how current EU rules are meant to apply to America/Godthab. Transitions occur at Mar lastSun 1:00u and Oct lastSun 1:00u, which should be equivalent to Mar Sat>=24 22:00s and Oct Sat>=24 22:00s.<br>
</div><div class="gmail_extra"><br clear="all"><div>--<br>Tim Parenti<br></div>
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