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Comment by viega | Hacker News Reader

I always use unsigned values and do:

  while (i-- != 0) { ... }

It's more clear than the most idiomatic way, which is to drop the explicit comparison:

  while (i--) { ... }

All of it is better than the clunky old for-loop syntax.

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if `i` ever gets modified inside the loop, and skips 0 (e.g., got decremented twice when it is at 1), then you might end up with an infinite loop?

Usually, this won't happen of course, but because `i` is not declared inside a for-loop, it must have been declared outside, and thus might even look like a regular variable that could be used by some "clever" coding to multipurpose it!

In any case, it's a niche worry i have, so i usually don't do it if i know there's a for loop that would do.

There is nothing clearer about your way unless someone is just starting with C.

'while (i--)k is a shortcut, which might seem terse when one first encounters it, it is a well-established and trivial to understand construct. On the other hand, your embellishment only adds pointless friction when reading the code.

Never use unsigned values as your loop counter variables if you can help it. It is way too easy to underflow, and no one needs to iterate more than 2^31 or 2^63 times. You will die before exhausting int64.

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