On Mon, Jun 11, 2018 at 3:10 PM Rob Cliffe via Python-Dev < firstname.lastname@example.org> wrote:
Skip, I think you have misunderstood the point I was making. It was not whether the loop variable should leak out of a list comprehension. Rather, it was whether a local variable should, so to speak, "leak into" a list comprehension. And the answer is: it depends on whether the code is executed normally, or via exec/eval. Example:
def Test(): x = 1 print([x+i for i in range(1,3)]) # Prints [2,3] exec('print([x+i for i in range(1,3)])') # Raises NameError (x) Test()
I (at least at first) found the difference in behaviour surprising.
Change 'def' to 'class' and run it again. You'll be even more surprised.