[EMAIL PROTECTED] (Paul Boddie) writes:
Well, I've been using Python for almost ten years, and I've managed to deliberately ignore descriptors and metaclasses quite successfully. I get the impression that descriptors in particular are a detail of the low-level implementation that get a disproportionate level of coverage because of the "hack value" they can provide (albeit with seemingly inappropriate application to certain problem areas).
I have exactly the same impression, but for me it's the reason why I feel uncomfortable with them. For example, I fear that a skilled package writer could create a module with surprising behaviour by using the magic of these constructs. I don't know Python well enough to get more specific, but flexibility almost always make confusing situations for non-hackers possible.
I know that such magic is inavoidable with dynamic languages, but descriptors will be used almost exclusively for properties, and therefore I think it would have been better to hard-wire properties in the interpreter rather than pollute the language with this sort of proto-properties (aka descriptors).
Certainly descriptors in the "wrong hands" could lead to confusing, unreadable code. But Python is a "we're all adults here" language, and so we have to trust other coders to be responsible. There are some very reasonable uses for descriptors which I don't believe are really confusing, for example the lazy property recipe:
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/363602
While writing too many descriptors is a code smell, the functionality is there as an implementation detail of new-style classes, and I'm quite happy that Python trusts me enough to expose this detail for when I need it.
STeVe -- http://mail.python.org/mailman/listinfo/python-list
