<div dir="ltr">Thanks for that. Looking at <a href="http://www.ietf.org/timezones/code/zic.c">the code</a>, it seems that:<div><ul><li>It <i>is</i> valid to specify Feb 29th if it's just in a single year which is a leap year</li>
<li>It's valid to specify Feb 29th even for a non-leap year, so long as we're moving to an earlier day-of-week value (we could even end up on Feb 22nd, for example). (It's not entirely clear to me that that's a good idea, but...)</li>
</ul><div>I think I can probably encode both of those rules fairly easily in my C# code - and the "move to the next leap year" rule is definitely wrong...</div></div><div><br></div><div>Jon</div><div><br></div>
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<div class="gmail_extra"><br><br><div class="gmail_quote">On 7 July 2014 20:33, Arthur David Olson <span dir="ltr"><<a href="mailto:arthurdavidolson@gmail.com" target="_blank">arthurdavidolson@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>Script started on Mon, Jul 07, 2014 3:31:25 PM<br>$ cat fake<br>Rule Fake 2014 max - Feb 29 2:00 1 D<br>
Rule Fake 2014 max - Oct 31 3:00 0 S<br><br>
Zone Fake 0 Fake F%sT<br>$ ./zic fake<br>"fake", line 4: use of 2/29 in non leap-year (rule from "fake", line 1)<br>$ exit<br>Script done on Mon, Jul 07, 2014 3:31:32 PM<br><br></div> @dashdashado<br>
</div><div class="HOEnZb"><div class="h5"><div class="gmail_extra"><br><br><div class="gmail_quote">On Mon, Jul 7, 2014 at 3:09 PM, 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:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">I'm just going through my <a href="http://nodatime.org" target="_blank">Noda Time</a> code for time zone handling, and I've noticed I'm being even more defensive than normal, by handling the situation where a time zone transition is specified to occur on the 29th of February - I skip forward or backwards to the nearest leap year.<div>
<br></div><div>This feels like it's overkill to me, and that it would be better just to prohibit this situation from occurring in my code, <i>if</i> it's widely accepted to be invalid data.</div><div><br></div><div>
Is there anything specifying the behaviour if such data is presented? I could try running the zoneinfo compiler myself, but I suspect it would take a long time to get all the tools sorted, and I wouldn't be certain of interpreting the outcome properly. If anyone just <i>knows,</i> that would save me a lot of effort :)</div>
<span><font color="#888888">
<div><br></div><div>Jon</div><div><br></div></font></span></div>
</blockquote></div><br></div>
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