Hi, Guido van Rossum wrote: > On Sun, Sep 7, 2008 at 12:15 AM, Stefan Behnel <[EMAIL PROTECTED]> wrote: >> Antoine Pitrou wrote: >>> Also note that Marc-André Lemburg (one of the authors of the unicode >>> implementation) is opposed to that change. See the discussion in the bug >>> tracker >>> issue for the details. >> From a Cython perspective, I find the lack of efficient subclassing after >> such >> a change particularly striking. That seriously bit me in Py2 when I tried >> making XML text content a bit more intelligent in lxml (i.e. make it remember >> what XML element it originated from). Having the same problem for unicode in >> Py3 doesn't sound like a good idea to me. > > Can you explain this a bit more? I presume you're talking about > subclassing in C
Yes, I mentioned Cython above. > I do note that the mechanisms that exist for supporting adding a __dict__ > to a str (in 2.x; or bytes in 3.x) or a tuple could be extended for other > purposes. I never looked into these, but this does not sound like it would impact subclassing. > Also, please explain why instead of subclassing you couldn't use a > wrapper class? (I.e. use containment instead of inheritance.) Because users will expect that the return values can be passed into anything that accepts a string, which is much more than you could catch with a wrapper class. There are tons of C-level APIs inside and outside of Python itself that require strings for certain operations and will not accept any other object. Just think of passing a wrapper object as type name of a newly created type. Stefan _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
