Making HTML 4.1 Also Comply with XHTML 1.1

[Ben Sharvy]

Is there a list of the changes you need to make to HTML 4.1 cose to
make it dual compliant, with XHTML 1.1 also?

[Darin McGrew]

I wrote:

You must also avoid empty elements (e.g., LINK, IMG) that cannot be
represented in a way that is valid for both HTML and XHTML.

Owen Jacobson <oj************ **@mx-deus.net> wrote: Oof. I missed that completely. Yeah, that's a big issue. For my own
information, is the following valid in XHTML 1.0? In HTML 4.01?

<link rel="stylesheet " href="pagestyle " type="text/css"></link>

In HTML, the closing </link> is invalid. You're trying to close a LINK
element that isn't open.

In XHTML, your example is valid, and is equivalent to

<link rel="stylesheet " href="pagestyle " type="text/css" />

(which is what Appendix C recommends).
--
Darin McGrew, mc****@stanford alumni.org, http://www.rahul.net/mcgrew/
Web Design Group, da***@htmlhelp. com, http://www.HTMLHelp.com/

"I used to do lots of dumb things, but I turned my life around 360 degrees!"

[Stan Brown]

In article <bj**********@b lue.rahul.net> in
comp.infosystem s.www.authoring.html, Darin McGrew
<mc****@stanfor dalumni.org> wrote:

Owen Jacobson <oj************ **@mx-deus.net> wrote:

Oof. I missed that completely. Yeah, that's a big issue. For my own
information, is the following valid in XHTML 1.0? In HTML 4.01?

<link rel="stylesheet " href="pagestyle " type="text/css"></link>
In HTML, the closing </link> is invalid. You're trying to close a LINK
element that isn't open.

In XHTML, your example is valid, and is equivalent to
<link rel="stylesheet " href="pagestyle " type="text/css" />
(which is what Appendix C recommends).

Now I'm confused. (This seems to be happening a lot lately.) I
understand that </link> is no valid HTML. But I thought the whole
point of Appendix C was to write markup that was valid HTML and
valid XHTML. The very first sentence of Appendix C is "This appendix
summarizes design guidelines for authors who wish their XHTML
documents to render on existing HTML user agents." True, that
doesn't say that the XHTML is valid HTML, but I thought that was
implied.

Are you saying that <link rel="stylesheet " href="pagestyle " type="text/css" />

is _not_ valid HTML?

--
Stan Brown, Oak Road Systems, Cortland County, New York, USA
http://OakRoadSystems.com/
HTML 4.01 spec: http://www.w3.org/TR/html401/
validator: http://validator.w3.org/
CSS 2 spec: http://www.w3.org/TR/REC-CSS2/
2.1 changes: http://www.w3.org/TR/CSS21/changes.html
validator: http://jigsaw.w3.org/css-validator/

[Tina Holmboe]

Stan Brown <th************ @fastmail.fm> exclaimed in <MP************ ************@ne ws.odyssey.net> :

understand that </link> is no valid HTML. But I thought the whole
point of Appendix C was to write markup that was valid HTML and
valid XHTML. The very first sentence of Appendix C is "This appendix
summarizes design guidelines for authors who wish their XHTML
documents to render on existing HTML user agents." True, that
doesn't say that the XHTML is valid HTML, but I thought that was
implied.

The keyword is "render". The implication is rather "Let's write XHTML
in such a way that tag-soup eating browsers will simply view this as
another addition to the menu and render away".

Usual caveats apply.

--
- Tina Holmboe Greytower Technologies
ti**@greytower. net http://www.greytower.net/
[+46] 0708 557 905

[Jukka K. Korpela]

Stan Brown <th************ @fastmail.fm> wrote:

But I thought the whole
point of Appendix C was to write markup that was valid HTML and
valid XHTML.
It might give that impression, perhaps intentionally.
The very first sentence of Appendix C is "This appendix
summarizes design guidelines for authors who wish their XHTML
documents to render on existing HTML user agents." True, that
doesn't say that the XHTML is valid HTML, but I thought that was
implied.
And maybe we were supposed to think that way. I know this is somewhat
negative thinking. But the XHTML specification really seems to avoid the
issue that XHTML and HTML are not compatible _at the level of
specifications_ , even if (almost all) browsers can be fooled to eat XHTML
when they actually digest HTML.
Are you saying that

<link rel="stylesheet " href="pagestyle " type="text/css" />

is _not_ valid HTML?

In a document with an HTML doctype, it makes the document invalid
except in a special case. The reason is that the construct is, by HTML
rules, equivalent to
<link rel="stylesheet " href="pagestyle " type="text/css">>
and data characters are not allowed inside a <head> element, so the data
character ">" would imply </head> and <body>. So if the rest is the
document body without a <body> tag, the document is valid (though its
content is probably not what the author meant, and this in turn is negated
by the fact that browsers don't actually play by HTML rules here).

--
Yucca, http://www.cs.tut.fi/~jkorpela/
Pages about Web authoring: http://www.cs.tut.fi/~jkorpela/www.html