Getting all constants within a class in python

class, constants, python, python-2.7

Solution

You'll have to filter those out explicitly by filtering on names:

[value for name, value in vars(CommonNames).iteritems() if not name.startswith('_')]

This produces a list of values for any name not starting with an underscore:

>>> class CommonNames(object):
...     C1 = 'c1'
...     C2 = 'c2'
...     C3 = 'c3'
... 
>>> [value for name, value in vars(CommonNames).iteritems() if not name.startswith('_')]
['c3', 'c2', 'c1']

For enumerations like these, you'd be better of using the `enum34` backport of the new `enum` library added to Python 3.4:

from enum import Enum

class CommonNames(Enum):
    C1 = 'c1'
    C2 = 'c2'
    C3 = 'c3'

values = [e.value for e in CommonNames]

Problem

I have a class which is essentially used to define common constants for other classes. It looks something like the following: ``` class CommonNames(object): C1 = 'c1' C2 = 'c2' C3 = 'c3' ``` And I want to get all of the constant values "pythonically". If I used `CommonNames.__dict__.values()` I get those values (`'c1'`, etc.) but I get other things such as: ``` <attribute '__dict__' of 'CommonNames' objects>, <attribute '__weakref__' of 'CommonNames' objects>, None ... ``` Which I don't want. I want to be able to grab all the values because this code will be changed later and I want other places to know about those changes.

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