- From: Leif Halvard Silli <lhs@malform.no>
- Date: Sat, 14 Mar 2009 06:44:44 +0100
- To: Robert J Burns <rob@robburns.com>, Dave Singer <singer@apple.com>, www-archive <www-archive@w3.org>, Charles McCathieNevile <chaals@opera.com>
-public-html
+www-archive
Dave, Rob + Charles (who brought <time> to our attention)
Supposing that the proleptic Gregorian calendar should be used in the
entire Julian period or so, then, with authors in mind, if Marthin
Luther's death on the the Julian 18th of February 1546, is recorded in
@datetime as 18th February, Gregorian - which is incorrect as it should
be 28th if it is Gregorian, then, "in the wild" we'll see errors in how
that wrong date is presented/perceived: as 8th of February if that dates
is "converted" to Julian. As "correct", historic *Julian* date if it is
*not* converted (even if it is noted wrong). Further, if it is correctly
noted as 28th February, Gregorian, then we will se that it isn't
converted to Julian, thus it will be presented as if he died on the
28th. This level of confusion is *only* possible for Julian dates.
Therefore Julian dates should be taken especially care of.
Either authors must be allowed to record the date in another format as
well as in the Greogorian format, where the other format has the role of
presentation (the name of the attributes are completely made up, but not
take completely out of the blue):
<time julian="0650-05-25" datetime="0650-05-27">25.5.650</time>
And perhaps even *only* in the Julian format - singling out that it _is_
Julian:
<time julian="0650-05-25" >25.5.650</time>
Or they must be allowed to have an attribute that informs that the
recorded date is not Gregorian
<time daysBehindGregorian="2" datetime="0650-05-25">25.5.650</time>
Or there must be something that tells that this date should be
*presented* as a Julian date:
<time julianPresentation="-2" datetime="0650-05-27">25.5.650</time>
The presentation info could be inside @datetime, or an extension to the
date format:
<time datetime="0650-05-27; Julian:-2;">25.5.650</time>
<time datetime="0650-05-27_-2;">25.5.650</time>
Or else we must decide that for dates from before the Gregorian calendar
started, the purpose of @datetime is *only* comparison and sorting -
*not* presentation. (Meaning that authors would have to use e.g. @title
to convey presentation.)
<time present-as-ISOdate="no" datetime="0650-05-27">25.5.650</time>
<!-- the October revolution -->
Because if we do not take care of Julian, then we will end up in the
dilemma: When is @datetime intended to be presented as a Julian date,
and when is it supposed to be presented as a Gregorian date? (Because,
@datetime is supposed to be presented - it isn't only a interchange
format, like in e-mail.)
Dave, I hope you see that we need to be able to tell how the number is
supposed to be perceived? The ISO date is supposed to be unambiguous in
the first place. However, we got to see that it isn't for the times and
places where the Julian has been used. Authors must be encouraged to
record dates in a standardized format. And then there must be some
incentives for them to do so. We should not rely on authors adding the
ISO date only because they reason that "it is probably good that I do
so". They must feel and see that they record something that it is
relevant and accurate to record. There must be immediate benefit, also
for them.
--
leif halvard silli
Received on Saturday, 14 March 2009 05:45:27 UTC