On Thu, Aug 20, 2015 at 2:54 AM, Thomas Güttler <guettliml@thomas-guettler.de> wrote:
I think it would be great to have properties for classes in Python2 and Python3
There are some "patterns" to get this working:
http://stackoverflow.com/questions/5189699/how-can-i-make-a-class-property-i...
http://stackoverflow.com/questions/128573/using-property-on-classmethods
... but an official solution would be more "zen of python".
I recently added my own implementation of this here: https://github.com/astropy/astropy/blob/master/astropy/utils/decorators.py#L... (which I think is pretty elegant--moreso than the ones on those SO links, but I'm biased :) However, my version is only for read-only properties. It could easily be extended to support writeable properties, but as pointed out elsewhere that requires the container class to have a custom metaclass :/
Do you think properties for classes would be useful?
Yes--given my recent experience in trying to implement this I feel like it should be supported in Python. Just as Python ships with a builtin classmethod, I think there should be a builtin classproperty that is special-cased to work without a custom metaclass. I think it's a special case that's special enough IMO.
If it works for classes, then it could be used for modules, too?
With a ModuleType subclass, sure, but that's a separate, and thornier issue :) Erik