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- From: Amy Lewis <email@example.com>
- To: xml-dev@XML.ORG
- Date: Sun, 18 Jun 2000 14:28:00 -0400
Because it ain't XML.
In a few responses in the FOs thread, it's been made clear that XSL FO
is intended as a high-performance page description language; reading
the list of working group members' affiliations makes it clear that
this is where the expertise (and hence the focus) is going to be. The
suggested alternative for a simple presentation language has been CSS.
I don't like CSS. I learned back-when, and still can't use it, because
it isn't supported well.
I believe that CSS is a dead end. That's fairly tendentious, I
suppose, but I have some reason to say it. It isn't an XML language,
so it provides no leverage of existing familiarity with tag-oriented
markup languages. Instead, it has the flavor of client-side scripting
language. Worse, from the point of view of implementation, developers
can't leverage the XML and XSLT parsers that they may already have
implemented; CSS requires an additional engine. My main reason for
calling it a "dead end," though, is that because it isn't XML, it has
to be "last in the chain". Using stylesheets, it has its own selection
language that has nothing to do with XPath, and is supposed to be
delivered directly to the rendering engine. If I combine XSLT and CSS,
I end up with an XML document in which the styling is all encoded in
the single attribute "style", and if I want to transform it any
further, I have a significant parsing challenge. I can't use my
validating XML parser to verify the correctness of my stylesheet; I
have to have something that understands CSS.
I want a stylesheet language that lets me leverage my familiarity with
XML syntax, and lets me reuse the tools that I already have for coping
with tag-oriented, tree-oriented languages. CSS isn't "part of the
I realize that the W3C continues to develop CSS, and that a part of the
reason for the focus of the XSL WG is probably so that it doesn't
conflict with that ongoing work. I realize that, after W3C has spent
*years* flogging this technology, it's likely to be embarrassed at the
prospect of abandoning it. But I *really* dislike being forced to use
CSS, and only barely refrained from titling this "CSS considered
harmful," which is probably just too over-the-top.
So, XSLFO ... sheesh. I agree with the need to be able to print
high-quality output. As a matter of fact, I think that the ability to
print barely-acceptable output would be an enormous advance over the
current situation. However, in my last-but-one job, the testers had an
irritating habit of applying the "mom and pop" test. That is, they
would ask "could a mom-and-pop shop (Ma and Pa Kettle's Online Special
Recipe Depot) use this software". XSL FO fails the test, in my
opinion. It's software that makes the user into Scarlett, always
depending on the kindness of strangers (who will develop the
interactive tools that will allow one to actually use the language,
since it's so large and variegated--over fifty elements, over two
hundred attributes that relate to those elements--that it isn't likely
to be easily learned).
I don't want to deprecate the work of the XSL FO committee. I just
don't see that it's going to meet my needs, judging both from the
current draft and from the focus of the comments expressed here in the
last week or two.
That leaves me with basically nothing, if I want to go out and help
Ma&Pa join the electronic revolution, using the vertical market schemas
for communicating with vendors of mash, pipe, and glassware, and their
own custom inventory/order language that's intended to interact with
humans hitting their site. There isn't anything that meets my needs,
because CSS isn't XML, and XSLFO is neither finished nor suitably
compact (I seriously doubt that there will be much stylesheet
generation using XSLFO without the aid of a software tool; I happen to
still like using text editors for generating this stuff). My printed
order forms don't *need* that level of control; my online presentation
is completely overwhelmed by that level of complexity. Perhaps the
XSLFO folks could produce a "core" outline, or follow the lead of the
schema folks and do a tutorial ... but it isn't the focus now, and
given the need to not appear to be trying to undermine CSS, it probably
won't be in the future.
I don't mind undermining CSS, though.
So, drawing on material from CSS & XSLFO, and from XLink, XSLT,
XPointer, and XPath, I've put up a really quick pass at a layout
vocabulary for XML, at
It may be that, in my dislike for CSS and disappointment with XSLFO,
I'm part of a vanishingly small minority, so that there's no point in
doing this. If so, I'll shut up after this. If there's interest, drop
me a line, and I can expand on the admittedly sketchy material that's
currently there (if you can't get to the doc using the above URL, then
try it - .txt + .html; that will mean I've revised it to pretty-print,
and there's been some level of positive response).
One last request: if you're going to flame me based on popular-cultural
icons, could you try to explain some of the referents? I haven't
watched network television for something like twenty years. I gather
that Scully and Mulder are actors in a television show about alien mind
control, that has an X in its name, and that this was prompted by the
abbreviation "first generation Xweb." That phrase made sense to me as
an abbreviation of "first generation XML-based web," which in turn
might stand for "initial stages of the transformation to a network
information infrastructure relying on XML over HTTP for content and
data delivery." I'm not quite sure where the alien mind control comes
in there (as opposed to XPointer, XML, XPath, XSL, Xthis, Xthat, and
Xtheother), although there does seem to be a mind-reading markup
language referenced from the Cover pages. On the other hand, my
friends seemed to get a kick out of trying to explain this to me, but
I'm afraid there may have been more noise than signal in the channel.
If it matters, I wasn't suggesting some sort of mind control web (that
wasn't being suggested, really, was it?).
Amelia A. Lewis firstname.lastname@example.org email@example.com
I stopped by the bar at 3 a.m. to seek solace in a bottle, or possibly a
friend. I woke up with a headache like my head against a board, twice as
cloudy as I'd been the night before. I went in seeking clarity.
-- Indigo Girls
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