On Thu, Feb 19, 2015 at 5:53 AM, Marko Tiikkaja <marko@joh.to> wrote:
Hi,
Commit 79af9a1d2668c9edc8171f03c39e7fed571eeb98 changed xpath handling with regard to namespaces, and it seems to be fixing an actual issue. However, it was also backpatched to all branches despite it breaking for example code like this:
do $$ declare _x xml; begin _x := (xpath('/x:Foo/x:Bar', xml '<Foo xmlns="teh:urn"><Bar><Baz>1</Baz><Bat>2</Bat></Bar></Foo>', array[['x','teh:urn']]))[1]; raise notice '%', xpath('/Bar/Baz/text()', _x); raise notice '%', xpath('/Bar/Bat/text()', _x); end $$;
The problem is that there's no way to write the code like this in such a way that it would work on both versions. If I add the namespace, it's broken on 9.1.14. Without it it's broken on 9.1.15.
I'm now thinking of adding a workaround which strips namespaces, but that doesn't seem to be easy to do, even with PL/Perl. Is there a better workaround here that I'm not seeing?
FWIW, I've been working around the bug fixed in that commit for ages by spelling my xpath like this:
I've modularized my XML handling functions so the source of 'data' is immaterial -- maybe it's a full document, maybe it's a fragment from a previous xpath() call -- and the referenced commit is going to make correct XPATH much more sane, readable, and maintainable. I, for one, welcome it wholeheartedly.
