Support Python expressions as part of XPath in py:match

[davidf@…]

It would be good to be able to specify an XPath as a Python expression (particularly where we're reusing it in multiple places, but this would also allow changing it from Python code) like so:

  <input py:match="${xpath_for_forms}"/>

or

  <input py:match="${create_xpath(valid_attrs)}"/>

[hodgestar+genshi@…]

Patch against ​http://svn.edgewall.org/repos/genshi/trunk r466 implements ${} expression handling inside py:match XPath expressions.

[hodgestar+genshi@…]

Patch includes a test. I'm not seeing any performance hit for this on either examples/bench/basic.py or bigtable.py.

[hodgestar+genshi@…]

All neither benchmark includes any match templates, so that's perhaps not surprising. :/

[cmlenz]

Hmm?

[Carsten Klein <carsten.klein@…>]

see also #91 which is actually a duplicate of this.