test: list comprehension name resolve should not include its own definitions
create a ListComprehensionFlow, to make the distinction between ForFlow and list comprehensions clearer
get rid of is_list_comp boolean in favor of a direct check of ListComprehensionFlow
fix issues with equal names before and after listcomprehension
make generator comprehensions work
tests for generator to tuple assignment as well as generator comprehensions
fix issues with generator comprehensions used directly with a send() call or something similar
fix issues with the previous commits (broken tests)
fix issues with tokens in expression list
hasattr test for static analysis, it's a common idiom.
hasattr checks working now, #408
list comprehensions should be able to serve as an input for dynamic params as well.
work in progress refactoring to make ListComprehension a sublass of ForFlow
fix list comprehensions. they were not implemented in a good way
further test for list comprehensions
*args without self but still an implicit self from a method decorator