This presentation was given at WWW9 on May 19, 2000. Opera 4.0 has since shipped and an
evaluations version can be downloaded. This presentation is kept
for archival purposes and serves as a sample file for Opera's
presentation mode. If you are using Opera 4.0 for Windows, press F11!
XML in Opera
Håkon W Lie
Chief Technology Officer
Opera Software
<howcome@opera.com>
Jon's invitation
Down here where only the truly dedicated will read it is another
solicitation. XML is becoming Establishment Technology; it's time
for some controversy. I would like to have one good inflammatory
presentation on the schedule. If you have an ax to grind and can
do so in an interesting and entertaining manner, send a proposal.
-Jon Bosak
Opera4
- HTML 4.0
- JavaScript 1.3
- HTTP 1.1
- SSL 2/3, TLS 1.0
- NNTP
- POP & SMTP
- CSS1 & CSS2
- XML
Why CSS?
I think CSS is perfectly usable and
extremely useful with XML, and there are existence proofs of this for anyone
who will look.
-Tim Bray
Opera4 XML features
- uses expat browser
- adds 80k to distribution
- used to parse XML, WML, ebook
Opera4 CSS2 formatting
- generated text
- attribute selectors
- pagination
- media-specific style sheets
- tables
- display: block, inline, list-item, run-in, compact
- floating elements
CSS3 features
- headers/footers
- multi-column
- writing-mode
Why not XSL?
- XSLT (XTL!)
- XFO
XSLT
- "the perl of the web"
- transformations necessary
- server side or client side?
- progressive rendering
- adds 300k?
- will generic semantics be available?
- server side!
XFO
- XML vocabulary for formatting
- no separation between content and presentation
- FONT tags
- Braille contractions
- formatting objects considered harmful
Specs written in XML
- WML
- Open eBook
- HWG's marked up Gutenberg
- generic markup
Semantics needed
- replaced elements
- link elements
- form elements
- the behavior of elements
Replaced elements
img {
-replace: attr(src);
}
Links
a {
-set-link: attr(href);
-use-link: current;
}
do, anchor {
-use-link: next;
}
go {
-set-link: attr(href);
}
Properties vs. XLink
- light-weight solution
- describes current formats
- HTML, WML, eBook
- for internal use
- extensions: longdesc, base
Is the dragon dying?
- XML is draconian
- expat encounters badformed WML?
- "encoding" attribute missing on XML declaration
- newlines before XML declaration
Opera4 availability
- Beta: Windows
- Alpha: Linux, Mac
- Q3: EPOC and BeOS