Merge request was proposed by xhess on GitLab, but the commit
had no content. I've solved it, possibly the same way.
For the initial commit:
Executing the second example at https://wiki.davical.org/index.php?title=PROPFIND
The "Depth: 2" header is the problem. Setting the depth header larger than 1
causes the function "compare_val_with_re" to be defined again. Now checking if
the function has already been defined fixes the problem.