To do what you are asking requires the perl interpreter to provide an "undo" feature.

This feature is not provided because it would slow down the program way too much. For every line of code that is run, perl would have to record what happened and how to undo that. That is just too much information to keep for the small amount of benefit that it would have for debugging.

That said, it is not impossible to do this, in fact "toy" languages exist which do it. Kayak is one of them. Here is a PhD. Thesis Proposal on the subject of reversable computers.

In reply to Re: debugger query: move execution point? by bunnyman
in thread debugger query: move execution point? by vnpandey

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