In addition to INS and DEL elements: DATED

As much as people will cringe, boo & hiss at the suggestion of yet 
another element for HTML, a good copanion to INS and DEL would
be a DATED element that indicates the enclosed material is dated, 
with optional start and end dates:

<!ATTLIST (DATED)
  %attrs
  begin      CDATA  #IMPLIED  -- when takes effect, ISO date form --
  expires   CDATA #IMPLIED   -- when no longer in effect, ISO date --
  >

The begin attribute (or maybe use datetime for consistency with INS
and DEL?) would specify when the information takes effect; expires
notes when the information is expired (but not necessarily the
entire page, which is why <META HTTP-EQUIV="Expires" ..> is not
applicable here).

An example:

<DATED BEGIN="1997-12-01T08:00:00Z" 
  EXPIRES="1997-12-14T17:00:00Z">Registration begins December 1st
    and ends December 14th.
</DATED>

Another example:

<DATED EXPIRES="97-09-01T12:00:00-05:00">The Chainsaw Garden
  show moves to a new time on September 1st...
</DATED>

The UA could render the text/markup in different colors (or add a
note that the material is outdated in text-based or autral browsers?)
depending on  whether the material is predated, active, or expired
(appropriate CSS pseudo-classes like dated:predated, dated:active and
dated:expired).

If the expiration date is before the begin date, then what the
browser does is undefined.

Hypothetical styles:

  dated:predated { font-style: normal; }
  dated:active { font-style: italic; }
  dated:expired { font-style: normal; text-decoration: strikeout; }

This does not provide an alternate text for when material is expired 
or not yet in effect. Nor is it a substitute for a substitute for 
maintenance (though it can allow maitenance software to point out 
outdated sections).

Comments?

Rob
---
Robert Rothenburg Walking-Owl (wlkngowl@unix.asb.com)
(Se habla PGP.) http://www.wusb.org/mutant/

Received on Wednesday, 20 August 1997 17:40:20 UTC