I will chime in and say I don't think deep copying is the best approach here. Use a global hash to store off-limits areas instead; you can localize individual keys of a hash as you descend, so Perl will do the backtracking for you naturally. This solution will most likely be much more efficient in terms of both time and space.

Makeshifts last the longest.

In reply to Re: Deepcopy of complex structures. by Aristotle
in thread Deepcopy of complex structures. by BrowserUk

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