On Jan 19, 2005, at 4:40, Walter Dörwald wrote:
M.-A. Lemburg wrote:
Walter Dörwald wrote:If you drop the base class for unicode, this already works.__str__ and __unicode__ seem to behave differently. A __str__ overwrite in a str subclass is used when calling str(), a __unicode__ overwrite in a unicode subclass is *not* used when calling unicode():
[...]
That's cheating! ;)
My use case is an XML DOM API: __unicode__() should extract the character data from the DOM. For Text nodes this is the text, for comments and processing instructions this is u"" etc. To reduce memory footprint and to inherit all the unicode methods, it would be good if Text, Comment and ProcessingInstruction could be subclasses of unicode.
It sounds like a really bad idea to have a class that supports both of these properties:
- unicode as a base class
- non-trivial result from unicode(foo)
Do you REALLY think this should be True?!
isinstance(foo, unicode) and foo != unicode(foo)Why don't you just call this "extract character data" method something other than __unicode__? That way, you get the reduced memory footprint and convenience methods of unicode, with none of the craziness.
-bob
_______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
