Demystifying Python Descriptors

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descriptor_writeup.ipynb

Good point -- I've made the fix. Thanks!

First of all, thanks for the great article, it's informative and easy to follow! I wanted to let you know the link posted under the "UPDATE" is actually dead at this point.

Also, I can't immediately see a "natural" way to combine multiple descriptors to enforce multiple constraints (say negative and even).. am I missing something? I'm asking purely out of curiosity.

The correct link seem to be this. If that doesn't work either, just go to the archives for January 2012 here and search for "descriptor".

And yes, it is indeed a great read, thanks for putting this together!

@ChrisBeaumont i observed a typo in the following code fragment. "-1" value needs to be changed to "-100"

m = Movie('Casablanca', 97, 102, 964000, 1300000) print m.budget # calls Movie.budget.__get__(m, Movie) m.rating = 100 # calls Movie.budget.__set__(m, 100) try: m.rating = -1 # calls Movie.budget.__set__(m, -100) except ValueError: print "Woops, negative value"

@ChrisBeaumont, @jaimefrio The link seems to be wrong again. ;-). I think the correct link is: https://mail.python.org/pipermail/python-list/2012-January/618572.html