Ah yes, I see what you mean:
class Test(): x = 1 print (x) # Prints 1 print([x+i for i in range(1,3)]) # NameError (x)
Anyway, I apologise for posting to Python-Dev on was a known issue, and turned out to be more me asking for help with development with Python, rather than development of Python. (My original use case was a scripting language that could contain embedded Python code). Thanks to Nick for his original answer.
On 11/06/2018 23:31, Eric Fahlgren wrote:
On Mon, Jun 11, 2018 at 3:10 PM Rob Cliffe via Python-Dev <email@example.com mailto: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.
http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient Virus-free. www.avg.com http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient