libxml2 实现了哪个 Schematron 版本?

Which Schematron version does libxml2 implement?

Libxml2 附带 Schematron module. Since Schematron evolved 很多我想知道 libxml2 实现大致匹配哪个版本。

quick look at the source code 开始,libxml2 使用命名空间 http://purl.oclc.org/dsdl/schematron,这意味着 ISO Schematron (2006)。但是有一个 TODO 评论说

divergences between the draft and the ISO proposed standard :-(

好像没有changes to the source code that address this. So it's possible that libxml2 only supports a draft version of the ISO standard (maybe Schematron 1.6?). I'd suggest to ask on the libxml2 mailing list可以得到肯定的答案