> It is documented already > > "If the <literal>PATH</> matches an empty tag the result is an empty string"
Hmm, okay. But what we have here is not an empty tag, but a tag that is completely missing. I don't think those two cases should be treated in the same way ...
this information is not propagated from libxml2.
> Attached new patch > > cleaned documentation > regress tests is more robust > appended comment in src related to generating empty string for empty tag
Thanks, I incorporated those changes. Here's v46. I rewrote the documentation, and fixed a couple of incorrectly copied&pasted comments in the new executor code; I think that one looks good. In the future we could rewrite it to avoid the need for a tuplestore, but I think the current approach is good enough for a pg10 implementation.
Barring serious problems, I intend to commit this later today.