[XML-SIG] Re: [Twisted-Python] Can anyone recommend a sensible XML parser for Python?
Fred L. Drake, Jr.
fdrake at acm.org
Sat Sep 7 03:14:40 EDT 2002
Uche Ogbuji writes:
> You see, this is why reporting such "bugs" early is helpful. I could have
> told you ages ago that it is a *bad* idea to call cloneNode on a Document
> Accordin to the DOM Level 2 spec:
> "And, cloning Document, DocumentType, Entity, and Notation nodes is
> implementation dependent."
That's no reason to think its a bad idea to implement it or need it,
just that you can't rely on it being supported by an arbitrary DOM
> I do agree that the confused error message is a glitch. Current PyXML CVS
> gives a more straightforward "sod off" :-)
Not quite; the previous message would have been raised calling
cloneNode() on a processing instruction as well. Or calling it with
deep=1 on a portion of the tree that contained a processing
instruction. That was a real bug, and not an arbitrary limitation.
> We choose not to allow it. Perfectly legal, and I think this is the right
Honestly, I think we should implement cloneNode() for Document, simply
because not doing so seems an unnecessary limitation. It is not for
the library to decide what is right for the application.
I agree that not supporting it is legal. The exception that is raised
is wrong: it should be xml.dom.NotSupportedErr.
> If you try going this route, I guarantee you'll still be trying to get the
> most basic things right six months from now.
Heck, we're still trying to get Expat right, and it isn't exactly the
freshest software around!
> This is the impetus for the Python-in-a-tie effort for Python
> proper. I do think we'd make a lot more friends if there were a
> matching PyXML-in-a-tie. It would mean companies would have to
That would be nice to have. First task: improve & integrate all the
random piles of tests out there! They should all be run when I type
"make check" at the top level, not just a handful.
> You pointed out one problem in cloneNode which, from what I gather,
> was mostly because you're abusing DOM. This had nothing to do with
It is not at all clear that this is an abuse of the DOM, as I
Fred L. Drake, Jr. <fdrake at acm.org>
PythonLabs at Zope Corporation
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