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Comment by theamk | Hacker News Reader

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)

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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.

Iterative aren’t a thing in C, where that code smell notion comes from.

What are you even talking about.

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.

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.

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)

Let's leave it there mate.

You're not the OP, you/me we're only guessing what he/she might've meant.

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