The simple example:
class A():
a = 1
b = [a + i for i in range(3)]
It will raise
NameError: name 'a' is not defined
However,
class A():
a = 1
b = a + 2
works.
What is the basic access rule in Python3?
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chenzhongpu
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2This works in Python 2.7 :o – Idos Mar 18 '16 at 14:39
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5I get `NameError: name 'a' is not defined`, not `TypeError`. – vaultah Mar 18 '16 at 14:40
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Working in python 2.7... – ml-moron Mar 18 '16 at 14:40
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3That isn't really the error that is caused. It would be a `NameError` if it weren't for the fact that you defined a function called `a` that you didn't tell us about ;) – zondo Mar 18 '16 at 14:41
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shoudn't any initialisation be done inside `__init__(self, ...)`? – Raf Mar 18 '16 at 14:41
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@Raf `a` and `b` are [class attributes](https://www.toptal.com/python/python-class-attributes-an-overly-thorough-guide) – idjaw Mar 18 '16 at 14:48
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http://stackoverflow.com/questions/13905741/accessing-class-variables-from-a-list-comprehension-in-the-class-definition – jmetz Mar 18 '16 at 14:49