[Tutor] Use flag to exit?

[Richard D. Moores]

On Thu, Jun 24, 2010 at 10:13, Alan Gauld <alan.gauld at btinternet.com> wrote:
>
> "Richard D. Moores" <rdmoores at gmail.com> wrote
>
>> How can I prevent
>>
>> Traceback (most recent call last):
>>  File "C:/P31Working/prime_to_biggest_prime_tutor3.py", line 45, in
>> <module>
>>   sys.exit()
>> SystemExit
>>
>> from printing? Or isn't using sys.exit() a good idea?
>
> Steven has already given you an answer to that although
> I'd add that I have no problems using sys.exit() in top level code.
> Just don't use it inside a function. Either raise an exception
> or return a value.
>
> If you are using it at the top level you may be running your code
> inside an IDE like IDLE or Pythonwin which always catches
> sys.exit(). That's OK, it's intended to print that message rather
> than exit so that you can debug the code if necessary, but it
> won't do it if you run the code from the OS prompt it will just
> exit silently as expected.

Thanks, Alan. And thanks also to Steven.

I think I much prefer accomplishing an exit by a function return, as I
do in <http://tutoree7.pastebin.com/QtAAtATd>, but if I wanted to use
sys.exit() in a script (but not in a function) I run inside IDLE or
Wing, how do I suppress the message? I'd just like to get that nailed
down.

Dick