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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=jackalmage@gmail.com href="mailto:jackalmage@gmail.com">Tab Atkins
Jr.</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=pentasis@lavabit.com
href="mailto:pentasis@lavabit.com">Pentasis</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Cc:</B> <A title=whatwg@whatwg.org
href="mailto:whatwg@whatwg.org">whatwg@whatwg.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, November 25, 2008 4:44
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [whatwg] Issues relating to
the syntax of dates and times</DIV>
<DIV><BR></DIV>On Tue, Nov 25, 2008 at 7:36 AM, Pentasis <SPAN dir=ltr><<A
href="mailto:pentasis@lavabit.com">pentasis@lavabit.com</A>></SPAN>
wrote:<BR>
<DIV class=gmail_quote>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Ian
Hickson wrote:<BR><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">While
I could see that maybe one day there'd be a use case for <time>
that<BR>would need historical dates, I really think that we'd have to
tackle other<BR>calendars in use today before looking at calendars that
aren't in use<BR>anymore. So I'd rather punt this for
now.<BR></BLOCKQUOTE><BR>While it is true that there are to many factors to
take into account regarding which calendar, which era, etc.<BR>I can also
imagine, (just brainstorming here) if I look at this example in the
spec:<BR><p>We stopped talking at <time datetime="2006-09-24 05:00
-7">5am the next morning</time>.</p><BR>This means I should
also mark up something like this:<BR><p>It was <time
datetime="???">5 seconds after the big
bang</time>.</p></BLOCKQUOTE>
<DIV><BR>"5 seconds after the big bang" is an exceedingly ill-defined time,
though. Currently you'd be lucky to peg it within a billion years of the
accurate time, ignoring any relativistic issues with timekeeping. This
was Ian's point about far-past dates being nearly never exact enough to
justify a machine-readable timestamp.<BR> <BR></DIV>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">There
are more factors to take into consideration in this example than just
calendars.<BR>So... Wouldn't it be far more efficient and convinient to have
a construction by which we can set a "base-date/time"? (something like the
base-url-thing). That way you can set the date/time to anything at all based
on a reference-setting. And this reference setting could be anything
(another calendar, a specific point in time (or perhaps even time-space) or
a relative reference. I don't think this would have to be dealt with by the
UA but can be done by scripting.</BLOCKQUOTE>
<DIV><BR>How does this solve the issue of the base time being too ill-defined
for a timestamp? Assuming you have a basetime of "the big bang", you can
certainly exactly specify exactly 5 seconds after, but how would you specify
the basetime?<BR><BR>You're just moving the issue one level back. This
doesn't solve the underlying issue that far-past dates aren't exact enough to
give them a timestamp. This problem requires an entirely different
solution, and trying to shoehorn it into a timestamp-based solution just gives
you two bad solutions.<BR><BR>~TJ<BR></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>No, actually you (and Ian) say it yourself. Dates
and times far-in-the-past can *never* be exactly defined. So we should instead
settle for a relative or approximate base if we cannot provide for an exact
one. In the example of the big bang I could set the base-time either to be
"big-bang" or "according to theory x". To name but a few. The advantage of
this is that the actual "exact" date/time can then always be re-calculated as
we acuire more knowledge about the date in question without having to
re-mark-up the whole thing. (but only if we want/need it).</FONT></DIV>
<DIV><FONT face=Arial size=2>The fact remains that dates and times can *never*
be exact. Besides why would we need that in mark-up language? What benefit is
it to HTML and UAs if dates and times are all based on one base?</FONT></DIV>
<DIV><FONT face=Arial size=2>I would much rather have a construct by which I
can at least set a date which makes sense in some way and I can rest easy to
know that this will "automatically" become more and more accurate (according
to the than used universal base-time-code) as science and knowledge
evolves.</FONT><FONT face=Arial size=2></FONT></DIV>
<DIV><FONT face=Arial size=2>I do not have to specify the base-time as you put
it, why do I have to? How would you define UTC for that matter? Sure there is
a definition for it, but that is also only valid based on other agreements
(UTC has no meaning when traveling at the speed of light between Jupiter and
Magellen I think). Besides, the UTC timing will also be "ill-defined" someday
in the future, so current date/times are no different (relativelly speaking)
from far-past-dates.</FONT></DIV>
<DIV><FONT face=Arial size=2>Another advantage of this is -I just realized-
that one could mark up time in a fictional article with fictional
dates.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>But, I will concede to the fact that this may
make things more difficult. But in that case I would ask for the definition of
the spec to be changed from "<FONT size=3><FONT face="Times New Roman">The
</FONT><CODE><A href="">time</A></CODE><FONT face="Times New Roman"> element
represents a date and/or a time." into something more restricting and exact
which at least represents the limitations of this element that are presented
in this discussion. Or better yet, drop the element as it makes no sense
(IMO).</FONT></FONT></FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Bert</FONT></DIV></DIV></BLOCKQUOTE></BODY></HTML>