Multidimensional comprehensions cannot access class variables except in the first for

[fengyangwang]

BPO	30577
Superseder	bpo-11796: Comprehensions in a class definition mostly cannot access class variable

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2017-06-06.00:13:57.148>
created_at = <Date 2017-06-05.23:56:16.901>
labels = ['interpreter-core', 'type-bug']
title = 'Multidimensional comprehensions cannot access class variables except in the first for'
updated_at = <Date 2017-06-06.00:13:57.147>
user = 'https://bugs.python.org/fengyangwang'

bugs.python.org fields:

activity = <Date 2017-06-06.00:13:57.147>
actor = 'zach.ware'
assignee = 'none'
closed = True
closed_date = <Date 2017-06-06.00:13:57.148>
closer = 'zach.ware'
components = ['Interpreter Core']
creation = <Date 2017-06-05.23:56:16.901>
creator = 'fengyang.wang'
dependencies = []
files = []
hgrepos = []
issue_num = 30577
keywords = []
message_count = 3.0
messages = ['295220', '295221', '295223']
nosy_count = 1.0
nosy_names = ['fengyang.wang']
pr_nums = []
priority = 'normal'
resolution = 'duplicate'
stage = 'resolved'
status = 'closed'
superseder = '11796'
type = 'behavior'
url = 'https://bugs.python.org/issue30577'
versions = ['Python 3.5']

[fengyangwang]

Reduced reproduction:

class X:
    r = [1, 2, 3]
    z = [(i, j) for i in [4, 5] for j in r]

fails with "NameError: name 'r' is not defined". The expected behavior would be for r to be resolved as the r in the class namespace. Note in contrast that

class Y:
    r = [1, 2, 3]
    z = [(i, j) for j in r for i in [4, 5]]

does not fail.

(Version 3.5.2 on Windows)

[fengyangwang]

By the way, in Python 2.7 at least, this was working.

[fengyangwang]

It looks like this is a duplicate of http://bugs.python.org/issue11796

Sorry for the noise.