> gsed ’s/;;/;/g' in.svg > out.svg

If a user has an SVG text element where ";;" goes into the document, then that'd make for an awfully awkward user experience and obscure bug to fix. For example: plot(rnorm(5), xlab=";;")

Meaning, the document must be loaded, parsed, and all style/class elements sanitized. KeenWrite performs real-time rendering of documents. The code to preview the document is shared by the code that exports to XHTML for ConTeXt to render. Effectively, this would be parsing the SVG document twice, which would bog down the previewer.

Changing the regexes in mlib-svg.lmt to forgive empty styles seems like the most efficient and flexible approach, which follows the robustness principle: "be conservative in what you send, be liberal in what you accept."

The specs for CSS styles are ambiguous as to whether property declarations are required:

I've since learned that Renjin uses JFreeSVG to produce the SVG file. I've logged a bug against JFreeSVG to avoid the double semicolon. However, this means waiting for a fix from JFreeSVG and then waiting for that fix to be integrated into Renjin. It'll probably be months before that'll happen. (The last release of Renjin was like 10 months ago.)

Thoughts?