Kristof Zelechovski wrote:
AFAIK, WebKit is not going to validate XML, they say it makes page load too
slow.
Yes, I can see validation would be a problem, and see little use for
that except local file testing. But I'm just talking about using the DTD
to access entities, not to do validation. While this does involve
another HTTP request (as do external stylesheeets, scripts, etc.),
browsers could, as they do with such files, cache the files.
Besides, entities introduce a security risk because it can contain
incomplete syntax fragments and they can open a path to XML injection into,
say,<![DANGER[<span title="&malicious-entity;">sweet kittens</span>]]>.
So XML processors often refuse to load cross-domain DTD or ENTITIES.
Then, cross-domain entities could be restricted... I'm just thinking one
should be able to at least have /some/ way to use them, even if you have
to save the file in the same domain.
There are several XHTML entities that are indispensable for authors, namely
those that disambiguate characters are invisible or are indistinguishable
from others in a monospaced typeface. These include spacing, dashes, quotes
and maybe text direction (deprecated). Converting them to their
corresponding characters deteriorates the editing experience in an ordinary
text editor. As far as codes for letters are concerned, text in a non-Latin
script would consist mainly of entities, which would make it extremely hard
to read, so this approach is not practical. An editor limited to the ASCII
character set would be better off using a transliteration scheme and a
converter.
Yes, if the whole document were written in that fashion, and it was not
a localization. But for those who are already using programs which
support non-Latin scripts, such documents may still take advantage of
entities (or even have the entities themselves be in a non-Latin
script). For example, my "Chinese XHTML" (
http://bahai-library.com/zamir/chineseXHTML.xml and
http://bahai-library.com/zamir/chineseXHTML.xsl ) (can view in Safari,
Firefox, or Opera), which allows tags, attributes, and CSS in Chinese
characters roughly equivalent to the XHTML tag names, as long as the
stylesheet is attached, could also use Chinese entities in the XML
document if such external doctypes were supported (the example uses one
in the internal subset). This raises another use for entities--a simple
introduction to preparing XHTML documents in all regards, regardless of
one's native language. (And I used entities in the XSL file too, thereby
highlighting another example of entities--the ability to automatically
and transparently share /all/ of my code, including localization code
for anyone who wished to make their own localization or borrow mine for
other uses.)
However, as some of the entities are indispensable, a DOCTYPE is required.
The browsers may support built-in entities but XML processors used to
process XHTML documents need not. Providing a set of the entities needed
in-line is easy;
If you mean providing them in each document, then that, while easy, is
already supported, but is a large use of bandwidth, and not to mention
quite a pain to have to copy into each document and maintain...
however, the problem is that some validating processors
like MSXML require that the DTD, if provided, should fully describe the
document; providing entities only is not supported by default and the
processor refuses to load the document. That means a DOCTYPE for XHTML is
necessary and should be provided by WHATWG (or by an independent party).
This DTD should be external in order to use parameter entities and, of
course, to make the document smaller. It cannot, of course, define all
nuances of XHTML, but an upper approximation would be sufficient.
The problem, of course, is maintenance, since XHTML is in flux. XHTML is
currently described formally by a RELAX NG grammar and maintaining a
separate DTD would double the work to do so it would be best to be able to
generate the DTD automatically. However, the converter I was advised to use
was unable to produce a DTD from the grammar because it is too complex for
the DTD formalism (of course).
Hmm... Good point. Still, it is surmountable...
Best regards,
Chris
Aside: Note that you cannot use DocBook with MSIE directly; a bug in the
default XSLT processor causes an error in initialization code. This kills
all transformations, whatever your document is. (I do not know about TEI.)
I've used XSL successfully before in IE, but haven't used it for some
time... Right now my "Chinese XHTML" which really did work for me in
Explorer before when I outputted in GB2312 is not working now, though
that may be due to the fonts on my system now.
Brett
