Re:Could someone clue me in ... (Score 1)

Having used LaTeX a lot, and having programmed a XSLT based publishing tool before discovering TeXmacs, I think I can help.

If you abstract all the prejudice and bigotry, the XML vs LaTeX debate just boils down to a few things:

• XML can be validated. That means that you can automatically process a XML document to be sure it contains only a specified set of structuring elements (they call them tags in XML, you call them commands and environments in LaTeX).
• The XML document structure is much more easy (generally) to parse and process automatically than the LaTeX document structure.

For SGML/XML folks, the main problem with LaTeX is that it allows the users to throw in just about anything in the document structure (including arcane and unparsable TeX wizardry). On the other hand, using a XML document format with a DTD restrains the user to a specific markup language, which is generally designed to allow only strutural markup. The point is in preventing people from doing the wrong thing in big documentation projects.

By the way, a DTD only define the markup language (the tags, and how they can be nested). In XML, the presentation is defined by a stylesheet, which can be CSS (only add some presentation info), XSL (can perform complex tranformations on the document structure), or something else.

What the XML folks here did not understand (no surprise, since they have not tried TeXmacs before flaming it) is that the user interface is so customizable that you can easily restrain the users to a specified markup language simply by not allowing them to input anything else.

Actually, you can (still) not prevent the user from putting legal structuring elements in illegal struture (invalid nesting) through copy-pasting, but:

• you can design the stylesheet to make illegal structures visually obvious, and
• since the TeXmacs document format is essentially (not exactly) Scheme (XML externalization will come soon), any real programmer can write a Scheme program to perform validation. Or if you know Perl, the document format is much more easily parsable than XML, so you could write validator in one week-end.

By the way, we would welcome such a contribution.