Line continuation for list comprehensions or generator expressions in python

Question

How are you supposed to break up a very long list comprehension?

[something_that_is_pretty_long for something_that_is_pretty_long in somethings_that_are_pret         


        

Answer 1

I'm not opposed to:

variable = [something_that_is_pretty_long
            for something_that_is_pretty_long
            in somethings_that_are_pretty_long]

You don't need \ in this case. In general, I think people avoid \ because it's slightly ugly, but also can give problems if it's not the very last thing on the line (make sure no whitespace follows it). I think it's much better to use it than not, though, in order to keep your line lengths down.

Since \ isn't necessary in the above case, or for parenthesized expressions, I actually find it fairly rare that I even need to use it.