<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>On 5 Mar 2009, at 15:17, Greg Houston wrote:</div><div><br class="Apple-interchange-newline"><blockquote type="cite"><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Personally, I think it would be an improvement to the datetime</font></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">attribute if it was valid for at least -9999 - 9999:</font></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica; min-height: 14.0px"><br></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica"><p> ... For these events to take place within a three week or so</font></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">period is simply impossible. The <time</font></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">datetime="-0004-03-13">eclipse</time> cannot be the one written in the</font></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">records of Josephus.</p></font></p> </blockquote></div><br><div>I agree that this would be an improvement, since it would make <time> compatible with hCalendar by using ISO8601 for datetime.</div><div><br></div><div>By remarkable serendipity, Paul Tarjan posted a presentation about searchmonkey today</div><div><a href="http://www.slideshare.net/ptarjan/semantic-searchmonkey">http://www.slideshare.net/ptarjan/semantic-searchmonkey</a></div><div>It mentions searching the web by date, where that information is available. So I would say a key use case for marking up historic dates is searching large archives by date eg. searching the National Maritime Museum archive for Elizabethan Navy records dating from 1595.</div><div><br></div><div>Wikipedia uses the date-time design pattern, from microformats, to mark up historic dates using ISO8601. In addition, TEI is widely used by archives and libraries to mark up texts, including ISO8601 dates (<a href="http://www.tei-c.org/Guidelines/P4/html/ref-DATE.html">http://www.tei-c.org/Guidelines/P4/html/ref-DATE.html</a>). Since authors are already publishing dates online, surely HTML5 should accept all ISO8601 dates rather than a limited subset, which requires additional processing on the part of authoring and publishing software to filter out valid dates that are invalid HTML5.</div><div><br></div><div>Regards</div><div>Jim</div><div><br></div><div><div>Jim O'Donnell</div><div><a href="mailto:jim@eatyourgreens.org.uk">jim@eatyourgreens.org.uk</a></div><div><a href="http://eatyourgreens.org.uk">http://eatyourgreens.org.uk</a></div><div><a href="http://flickr.com/photos/eatyourgreens">http://flickr.com/photos/eatyourgreens</a></div><div><a href="http://twitter.com/pekingspring">http://twitter.com/pekingspring</a></div><div><br class="khtml-block-placeholder"></div></div></body></html>