XPath-aware taxonomy querying support. In TQA no taxonomy XPath awareness is anywhere outside of this namespace.
This implies that all of TQA outside of this namespace (and the xpath namespace) can be used without the need for
any XPath processor. Everything inside this namespace does need an XPath processor, though.
Dependency on XPath processing for taxonomy querying and processing is not without its costs:
Some XPath expressions may be somewhat brittle and give inconsistent results among XPath processors
All prefixes used in XPath expressions must be bound to namespaces
The backing element implementation used is coupled to the XPath processor used. In practice, use Saxon for XPath processing and backing elements
Configuration of the XPath processor may be sensitive, not only w.r.t. namespaces, but also w.r.t. the base URI, etc.
XPath-aware taxonomy querying support. In TQA no taxonomy XPath awareness is anywhere outside of this namespace. This implies that all of TQA outside of this namespace (and the xpath namespace) can be used without the need for any XPath processor. Everything inside this namespace does need an XPath processor, though.
Dependency on XPath processing for taxonomy querying and processing is not without its costs: