2 ms·

I’ve never ever heard while described as a smell, or even slightly smelly. Care to explain?

• polonbike 2mo ago
  If you can smell it, there's something fishy in the neighborhood
• theamk 2mo ago
  I assume OP refers to the cases where "while" is used to re-implement existing operations... imagine finding code like this: i = 0 while i != len(todo): process(todo[i]) i = i + 1 sure, there may be a good reason to implement things this way (maybe "todo" grows during iteration?), but maybe not, and then the loop should be instead simplified to: for value in todo: process(value) (as an aside, this is exactly the case where the comments are required: "# not using for loop because todo might grow" will make it clear it's an intentional decision and not hallucination or something written from ignorance)
  • grebc 2mo ago
    You can use iterators in a while loop like your for example, making it look as clean as the for. I feel like this is a case of personal preference over actual issue.
    • adastra22 2mo ago
      Iterative aren’t a thing in C, where that code smell notion comes from.
      • grebc 2mo ago
        What are you even talking about.
    • theamk 2mo ago
      you mean like that? todo_iter = iter(todo) while True: try: value = next(todo_iter) except StopIteration: break process(value) or like that? todo_iter = iter(todo) # Note: assume "todo" does not contain None while value := next(todo_iter, None): process(value) I'd say neither of those are as clean as a simple for loop: for value in todo: process(value) and yes, that's the case of a personal preference, although I'd bet a lot of Python programmers will share that preference with me. That's what "code smell" means, after all - it's not a bug which is clearly incorrect, it's a code which is best avoided based on reviewer's personal experience.
      • grebc 2mo ago
        Your for loop is using an iterator of some kind. Just because it’s hidden in your language of choice doesn’t mean it’s not there. While/for can achieve the same thing, sometimes while is more practical as the steps to complete are unknown. But sure, stick your simple iterating a fixed collection as why it demonstrates while is a lesser language feature.
        • theamk 2mo ago
          I think your arguments would be much stronger with some actual code samples. Usually, when the same code can be written either as range-based "for" or as a "while", the "for" will look better and have fewer possibility of bugs. If you have examples otherwise, I'd like to see them. (Note I am specifically talking about range-based/iterator-based "for", not the C's variant. Nor am I talking the cases where the "for" is hard to use, like when the size might change at runtime)
          • grebc 2mo ago
            Let's leave it there mate. You're not the OP, you/me we're only guessing what he/she might've meant.
• d--b 2mo ago
  Probably because while is the source of many infinite loops, and because it’s sometimes faster and more rigorous to compute the length ahead of going into the loop. That said, I personally don’t think it’s smelly at all.
• deleted 2mo ago
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