[Python-Dev] Descriptor write-up [Draft: Please comment]

[Guido van Rossum]

(I'd like to review this more carefully when I have more time, but one
thing jumped out at me:)

[Phillip Eby]
> It would be a good idea to add some information about "data" and
> "non-data" descriptors, and the differences of how their attribute
> lookup is processed.  I recently posted here about the "attribute
> lookup process" or something to that effect, which covered this.
> Understanding data vs. non-data descriptors is important if you want
> to do pretty much anything with descriptors beyond what property()
> does.

Note that I recently changed the treatment of data descriptors by
super() in 2.3.  typeobject.c rev 2.227/2.228:

----------------------------
revision 2.228
date: 2003/04/16 20:01:36;  author: gvanrossum;  state: Exp;  lines: +1 -1
Sigh.  The crucial change was still missing from the previous
checkin. :-(
----------------------------
revision 2.227
date: 2003/04/16 19:40:58;  author: gvanrossum;  state: Exp;  lines: +10 -4
- super() no longer ignores data descriptors, except __class__.  See
  the thread started at
  http://mail.python.org/pipermail/python-dev/2003-April/034338.html
----------------------------

--Guido van Rossum (home page: http://www.python.org/~guido/)