start interactive mode on a specific script line

Question

I need to run my Python script as usual, but I want to stop execution on a specific line and start interactive mode.

In other words, I want to be able to check the value of all my variables at that point, and continue myself from there on python's command line.

How can I do this?

As long as you are trying to debug your code, the methods in the answers are the way you should go. If you actually need this sort of functionality as a user rather than as a developer of your script, you should be looking at ways to take user input during script execution or reorganizing your code in to functions, methods, and modules. — Silas Ray, Aug 03 '12 at 13:25

score 23 · Accepted Answer · answered Aug 03 '12 at 13:17

23

This can be done with the code module. The easiest way is to call code.interact().

answered Aug 03 '12 at 13:17

Sven Marnach

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Are you sure? It only looks like it opens a python shell, and that's it. I can't lookup any variables that I defined before `code.interact()` in my code, so I don't really see how to use this function. – Ricky Robinson Aug 03 '12 at 13:25
11

@Ricky You must use the `local` argument: `code.interact(local=locals())`. – Lauritz V. Thaulow Aug 03 '12 at 13:26
With autocomplete features too: https://stackoverflow.com/a/50918009/1045199 – Daniele Ricci Oct 27 '22 at 20:29

score 9 · Answer 2 · answered Aug 03 '12 at 13:17

9

Use a debugger and add breakpoints. Do you use an IDE? All the major IDEs have debugger support. From the CLI, you can use pdb.

answered Aug 03 '12 at 13:17

Silas Ray

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score 5 · Answer 3 · answered Aug 03 '12 at 13:20

Not exactly what you're looking for, but you can easily have your program break out to pdb (the Python debugger) by adding this line wherever you want your program to break out: