Loop labels are rare, but they lead to much simpler/clearer code when you need them. Consider how you would implement this kind of loop in a language without loop variables:

'outer: while (...) {
    'inner: while (...) {
        if (...) {
            // this breaks out of the outer loop, not just the inner loop
            break 'outer;
        }
    }

    // some code here
}

In C/C++ you’d need to do something like

bool condition = false;
while (...) {
    while (...) {
        if (...) {
            condition = true;
            break;
        }
    }
    if (condition) {
        break;
    }

    // some code here
}

Personally, I wouldn’t call it ugly, either, but that’s mostly a matter of taste

You used macro_rules, which is not common at all. Most rust files don’t contain any macro definition.

This code doesn’t even compile. There is a random function definition, and then there are loose statements not inside any code block.

The loop is also annotated, which is not common at all, and when loops are annotated it’s a blessing for readability. Additionally, the loop (+annotation) is indented for some reason.

And the loop doesn’t contain any codeblock. Just an opening bracket.

Also, the function definition contains a lifetime annotation. While they are not uncommon, I wouldn’t say the average rust function contains them. Of course their frequency changes a lot depending on context, but in my experience most functions I write/read don’t have lifetime annotations at all.

Yes, what you wrote somewhat resembles rust. But it is in no way average rust code.