Question about Exit()

Ignition
1

Version 8.1.19
I have a script running:

if record is None:
   Exit()

The script does exit, but the script also throws an error saying Exit undefined.
What is the correct exit?

2

I always use return where possible. Luckily, all perspective events are setup as def functions, so you can just return to exit the script. When I did use exit() it was

import sys
sys.exit()
2 Likes
3

Could you tell me the difference and advantage?

4

sys.exit() and the Java equivalent aren't designed to return early from a method, they're designed to end the execution of the program, and the only reason your Ignition Gateway / JVM doesn't cease to exist after that is because we've hooked into prevent it.

It's not meant for what you're using it for.

5 Likes
5

Does that mean Return is best?

6

Yes, return, or in some weird contexts where you can't just return, guard your logic with some kind of condition.

In your original example, it would just be:

if record is not None:
  # do logic
3 Likes
7

Careful! It's return.

3 Likes