Controversial programming opinion of the day: not knowing implementation details will come back to bite you, overexposure is better than underexposure.
Anyway, I think the basic idea is just a small extension of being able to pause the program counter, change stuff, do something else, and at one's option continue where one left off, all without requiring a debugger. Nothing new if you've been exposed to the Lisp world. Typical examples of utility being recovering from longComputation() then failing without repeating work and hot-fixing a long-running server process. I agree this example isn't a very good one, I like your design you commented on for this problem better, I think in this case even "an error in parsing a line is not exceptional" would suffice in defeating the example. (Though in Python even syntax errors are implemented with exceptions, so...)
Anyway, I think the basic idea is just a small extension of being able to pause the program counter, change stuff, do something else, and at one's option continue where one left off, all without requiring a debugger. Nothing new if you've been exposed to the Lisp world. Typical examples of utility being recovering from longComputation() then failing without repeating work and hot-fixing a long-running server process. I agree this example isn't a very good one, I like your design you commented on for this problem better, I think in this case even "an error in parsing a line is not exceptional" would suffice in defeating the example. (Though in Python even syntax errors are implemented with exceptions, so...)