I can remember there was already a discussion about this. And somebody 
proposed version 4 which is the best version I think.

Lachlan Hunt wrote:
b) It would mean that authors would have to take care that they wrote 
the date, following the format < exactly.  If an error was made, such as 
using '-' instead of ':', or omitting the T, or anything else, user 
agents may find it useless, and unable to process.

indeed but isn't that the same about forgetting a slash in a tag like 
<img src="foo" alt="bar" /> ?

Kind regards,
Jeroen


Lachlan Hunt wrote:

>
> Hi,
>  I would like to propose that XHTML implement a <datetime> element for 
> the purpose of rendering, obviously, dates and times.  I have noticed 
> some messages in the archives from a few months ago that mention 
> various date tags and formats, but none that I thought provided a 
> really good option.
>
> I have come up with several alternatives for this.
>
>
> Version 1:
>  The first places each field in a separate tag, as follows:
>
> <datetime calendar="gregorian" locale="au" tz="+10:00">
>    <day>Tuesday</day>
>    <date>28</date>
>    <month>10</month>
>    <year era="CE">2003</yr>
>    <time>13:10:15</time>
> </datetime>
>
> This has the advantage that older browsers that won't support the tags 
> will still render the content such as:
> "Tuesday 28 10 2003 13:10:15"
> which is atleast readable, though not perfectly formatted.  However 
> new browsers that do understand the tags will be able to apply, (also 
> older browsers that support CSS, if it provided by the author) will be 
> able to format the date in a presentable manner such as:
> "Tuesday, 2003-10-28 13:10:15"
>
>  Plus, browsers from other languages will see the calendar, locale and 
> tz (timezone) attributes and be able to perform calculations, or other 
> formatting to present the date in the user's preferred format, or even 
> convert to a different calendar.  xml:lang may also be used here to 
> specify the language, if it is different from the rest of the document.
>  The era (which would default to CE) attribute also allows historians 
> to write dates as BCE.
>
>  Note: I am proposing the use of CE (common era) and BCE (before 
> common era), instead of AD and BC because of the relationship of the 
> latter to christianity.
>
>  It may also be an option to use <hour>, <min> and <sec> tags, rather 
> than just the single <time> tag, but it may be unnecessary to break 
> time down that far.
>
>
> Version 2:
>  Alternatively, this could be written with each field as attributes, 
> and have default text, for rendering in older user agents, within the 
> tags.
> Using CSS, this default content could be hidden, as in the <object> 
> tag, for example, and use the attributes when printing the date, or 
> perform conversions before rendering by the browser.
>
> <datetime calendar="gregorian" locale="au" era="CE" year="2003" 
> month="10" day="Thursday" date="30" hour="13" min="10" sec="15" 
> tz="+10">Thursday, 10 October 2003, 13:10:15</datetime>
>
>  Possible CSS to render this could be written like this (or some other 
> variant):
> datetime:after {
>    content: attr(day) + ", " + attr(date) + "-" + attr(month) + "-" + 
> attr(year) + ", " + attr(hour) + ":" + attr(min) + ":" + attr(sec);
> }
>
>
> Version 3:
>  The third version simply specifies the calendar, locale, era and tz, 
> along with a format, as follows:
> <datetime calendar="gregorian" locale="au" tz="+10:00" era="CE 
> format="dddd, dd-MM-yyyy, HH:mm:ss">Tuesday, 30-10-2003, 
> 13:10:15</datetime>
>  This would allow user agents to understand the format that the date 
> has been written in, and allow alternative rendering, or conversions 
> to be performed.
>
>
> Version 4:
>  My final version simply uses an attribute that specifies the 
> international format, with default text rendered within, as before.
>
> <datetime datetime="2003-10-28T13:10:15+10:00">Tuesday, 10 October 
> 2003, 13:10:15</datetime>
>
>  However, I see two problems with versions 3 and 4:
> a) The browser would need to support this tag to be able to reformat 
> the date in any way.  I'm not aware of any css that can process a 
> string like this ("2003-10-28T13:10:15:00+10:00") to seperate content, 
> reformat and display.
>
> b) It would mean that authors would have to take care that they wrote 
> the date, following the format exactly.  If an error was made, such as 
> using '-' instead of ':', or omitting the T, or anything else, user 
> agents may find it useless, and unable to process.
>
>  Thus, I prefer either my first or second alternative because it 
> clearly seperates each field, making it easier for authors, and CSS 
> designers to format.  Perhaps some combinations of these four 
> alternatives that I have not considered could be used.
>
>
>
>
>

-- 


-------
<Greetz
  from="Jeroen Budts"
  e-mail="jeroen@lightyear.be
  url="http://www.lightyear.be "
  blog="http://www.teranex.tk "
/>