[XML-SIG] Finding _xmlplus in Python 2.3a2

Martijn Faassen faassen@vet.uu.nl
Sun, 2 Mar 2003 17:51:43 +0100

Uche Ogbuji wrote:
> I've stayed out of the _xmlplus thread because I really don't feel strongly 
> enough about the issue one way or another (nor did I when the initial 
> discussions took place).
> I understand that _xmlplus can be confusing when problems come abut, but on 
> the other hand, it would seem to me the best approach is to just try to avoid 
> those problems in the first place.  I also wonder that the proposed change is 
> too disruptive, given all the extant code that might depend on the ld 
> arrnagement.  On the flip side of that, I'm usually less of a stickler for 
> backwar compat than most if it involves a chaneg that does the right thing.
> So does ditching _xmlplus even do the right thing?  Is there so little 
> discssion about this here because so few care?

I don't know why there is so little discussion about this; perhaps because
everybody who could care isn't aware of the situation -- it's not like
it's very obvious to people, even to people who use the XML facilities.

I think ditching _xmlplus is the right thing, as it *causes* problems, it's not
only confusing when problems come about from some other source. It's rather 
difficult right now; your application might be working with core Python,
and if you install PyXML, it breaks. Or if you upgrade it. Oddly enough,
you might not even be aware that an application you build depends on
PyXML at all (you happened to had it installed, that's all, but were reading
the standard library reference and a dependency on some bug/undisclosed API
crept in). And then you find out later.

This isn't just theoretical, I've seen this happen to several developers.
These developers use PyXML but have no clue about the mysteries of _xmlplus,
and who can blame them..

Anyway, there's a cost for migrating to a saner solution, but changing around
a few imports isn't a big deal after all. PyXML has had far more damaging
problems (as more subtle) during upgrade than that in the past. :)