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advanced patterns when using break with while loops in Python 3.10

👀 Views: 26 đŸ’Ŧ Answers: 1 📅 Created: 2025-07-24
python loops debugging Python

I've encountered a strange issue with I've tried everything I can think of but I'm working on a personal project and I'm working with an unexpected behavior with a `while` loop in Python 3.10 that I need to seem to explain..... My goal is to process a list of numbers and stop the loop when I encounter a negative number. Here's the code snippet I'm working with: ```python numbers = [1, 2, 3, -1, 4, 5] index = 0 while index < len(numbers): if numbers[index] < 0: break print(numbers[index]) index += 1 ``` The output I'm expecting is: ``` 1 2 3 ``` However, I'm seeing the output: ``` 1 2 3 -1 ``` It seems like the loop is not breaking when it encounters the negative number. I have verified that the list itself does contain the negative number, and I'm not changing the list during iteration, so I don't understand why it isn't working as expected. I've also tried using `print` statements to debug, confirming that `numbers[index]` is indeed `-1` when `index` is 3, yet the loop continues to process. This behavior is inconsistent with my understanding of how the `break` statement should operate within a `while` loop. Is there something I'm missing, or could this be a bug in Python 3.10? Any insights or suggestions would be greatly appreciated! Is there a better approach? This is part of a larger mobile app I'm building. Any ideas what could be causing this? What's the best practice here?