One of the questions I’ve not yet answered for my own purposes is how to handle multiple human languages for documents containing MathML. I’m beginning to think my initial approach was a bit naive.
Initially, I had planned on a parallel markup scheme:
<semantics encoding=”MathML-Content”>
<!– … –>
<annotation-xml xml:lang=”en-US” encoding=”MathML-Presentation”>
<!– … –>
</annotation-xml>
<annotation-xml xml:lang=”fr-FR” encoding=”MathML-Presentation”>
<!– ..

. –>
</annotation-xml>
<!– … –>
</semantics>
However, if the parent document itself is a multilanguage document, this may not work very efficiently.
For example, if the document follows the conventions the W3C currently suggests, then a CSS stylesheet which hides the user’s non-native languages:
*:not([xml|lang=”en-US”) {
display: none;
}
would lose that whole fragment if it were in a section of the document designated fr-FR.
The solutions to this are at the moment non-obvious. Certainly I haven’t figured out a universal solution. (I am proceeding on the assumption that the browser is receiving the document post-processing from the server, with multiple languages in the document itself.) For all I know, Mozilla may already hide content that’s not from the native user’s language. Again, this is bad if the entirety of the MathML expression resides in one fragment.
I may have a partial solution. Instead of parallel markup contained in a single MathML expression, I might be able to spread it out:
<html:div style=”display:none;”>
<semantics encoding=”MathML-Content”>
<!– … –>
</semantics>
</html:div>
<!– later –>
<html:div xml:lang=”en-US”>
<semantics encoding=”MathML-Presentation”>
<!– … –>
</semantics>
</html:div>
<!– later –>
<html:div xml:lang=”fr-FR”>
<semantics encoding=”MathML-Presentation”>
<!– … –>
</semantics>
</html:div>
I’m looking for additional ideas on making XML/HTML documents truly international… and possibly refinements of this idea.