<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<div class="moz-cite-prefix">On 1/29/19 8:43 AM, Tony Finch wrote:<br>
</div>
<blockquote type="cite"
cite="mid:alpine.DEB.2.20.1901291339310.18720@grey.csi.cam.ac.uk">
<pre class="moz-quote-pre" wrap="">There's a common error (which is embedded in the iCalendar specification,
so it's s difficult error to avoid) of recording future times as time +
timezone name, instead of time + place. Of course, the mapping from place
-> timezone name is not stable...
</pre>
</blockquote>
One thing to note is that the mapping from place to time zone is
also not necessarily unique, and the mapping from place to relevant
political/cultural entity is <i>also</i> not necessarily stable.<br>
<p>I think there's actually no right way to do this, at least not at
the moment, because the whole thing is built on shifting sands and
we're not able to maintain a registry of all possible adjudicating
bodies for timekeeping that will ever exist.</p>
<p>One thing that<i> </i>could help with this problem and that <i>might</i>
be scoped well for this project to do, though, would be to ship a
machine-readable data structure that indicates something about the
history of time zone boundaries. So one example of this could be
that Asia/Qyzylorda split into Asia/Qyzylorda and Asia/Qostanay
recently. What this means is that anything that started using
Asia/Qyzylorda before the split is now ambiguous and may need to
be manually reallocated to Asia/Qostanay. Having a way to
programmatically detect when these ambiguities arise might help
things.<br>
<br>
Maybe this already exists (outside of the changelogs) and I missed
it, though.<br>
</p>
</body>
</html>