How do I reset a Python tree iterator for multiple loops?

[Michael.M]

I’m trying to implement a custom iterator for a tree structure in Python, and my `__next__` method is raising a `StopIteration` correctly, but it feels like the iterator state gets stuck after the first full traversal. I’m not sure if my `__iter__` method is properly resetting something, or if I’m misunderstanding how a single iterator object is supposed to work across multiple loops.

[Jeffrey_C]

I ran into this too. A single iterator object felt like it would get stuck after the first full pass. What helped was treating __iter__ as returning a fresh object for each loop, or making a clear reset method that reinitializes the internal stack and pointer when a new loop starts.

[CamilaFJ]

Yeah, I tried to reset in __iter__ by rewinding the pointer, but then the next for loop started from the end anyway. It sometimes feels like the runtime caches the iterator somewhere and ignores Python-level resets.

[Gary73]

I keep worrying the real issue might be the traversal logic rather than the iterator protocol. If you hit a leaf and pop off the stack, you still have to unwind correctly. I added some prints to confirm which nodes get visited, and it helped me see where it stalled.

[AmeliaG]

One more thing I did was check what happens if someone holds onto the iterator and starts another loop later. For loops typically fetch a new iterator, but if you assigned it to a variable and reused it, you can end up with a stale state. Not sure if that matches your case, but it happened to me.