XML and HTML
Cross-Pollination:
A Bridge Too Far?

HTML/XML Task Force

• How can XML/HTML toolchains be used to consume HTML/XML?
• How can islands of XML/HTML be embedded in HTML/XML?
• How can XML be made more forgiving of errors?
• http://www.w3.org/TR/html-xml-tf-report/

Cross-Pollination

• Forget about your angle brackets
• Look at the ideas

XML in the browser

<?xml-stylesheet href="xmltest.css"?>
<doc>
  <title>Title</title>
  <para xml:id="test">Testing.</para>
</doc>

XML in the browser

• Browser reads XML, renders with CSS
• Works today, mostly:
• Styling a complete vocabulary not so hard
• Images are theoretically possible

XML in the browser: Scripting

<?xml-stylesheet href="xmltest.css"?>
<doc>
<title>Title</title>
<para xml:id="test">Testing.</para>

<script xmlns="http://www.w3.org/1999/xhtml">
//<![CDATA[
var txt = document.createTextNode("Script test");
var p = document.getElementsByTagName("para")[0];
p.replaceChild(text, p.firstChild)
//]]></script>
</doc>

XML in the browser: Scripting (continued)

• HTML scripts are interpreted
• Scripts can access the XML DOM
• The case for xml-script (or lack thereof)

XML in the browser: Linking

• Very vocabulary dependent (XLink not widely adopted, Norm: sigh, Robin: yay!)
• Linking can be emulated with script
• Declarative links could be useful

XML in the browser: Accessibility

• Theoretically, at least as good as HTML
• In practice, much worse

XML in the browser

• Hard to justify.
• The browser vendors aren't interested.
• Most developers aren't interested.
• Use a tool designed for it, such as Saxon-CE

XPointer and CSS

• XPointer can point inside documents
• CSS can select nodes inside documents
• Maybe the two can meet?
• http://simonstl.com/articles/cssFragID.html

XPointer and CSS: Examples

• http://example.org/foo/#css(.rfc2119)
• http://example.org/foo/#css(section>h2)
• http://example.org/foo/#css(article p:nth-child(3))

Implementing FO

• pdf.js supports PDF directly in the browser
• It has helped improve browsers in finding gaps
• What's missing to implement FO?
• It would be much nicer than using PDF...

Compilation to JS

• Saxon Client Edition
• XML Pipeline Processing in the Browser

SVG's Switch

• SVG was absorbed into HTML (including syntax-wise)
• What are the results?
• Should it go further?

Distributed Extensibility

• XML had potential for DE that was almost never used
• HTML is blamed for not having DE
• But is it true?

JS-SLT

• Javascript has proven powerful at markup transformation
• So has XSLT, with a seductive model
• Could we marry these two?

JS-SLT: Code

var sheet = require("jaspilite").sheet()
,   $     = require("jquery");
sheet.template("section", function () {
    return $(this)
              .apply()
              .wrapIn("<div class='section'/>");
});
var $out = sheet.run("my-document.html");
console.log($out.html());
      

Schemata on the Web

• HTML has a limited validation ecosystem
• But it could be useful at times
• We always need more schema languages

CSS Schema!

CSS Schema: Code

@rule head {
  title {
      assert:  "Page does not have a title.";
  }
}
@rule body {
  :scope > div.std-top {
      assert:   "Missing page top component.";
  }
}

Conclusions

• Characterizing the relationship between the XML and HTML communities is largely a matter of perspective
• Far enough away: they're nearly indistinguishable
• Close enough: there's almost no common ground

Conclusions (2)

• Forget: XML on the Web
• Embrace: XML's good ideas on the Web

Questions?

Thanks!