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Comment by amavect | Hacker News Reader

Post-increment inverts to pre-decrement, but for-loops don't support proper syntax sugar for pre-decrement.

  for(size_t i = 0; i < size; i++){
    // loop body
  }
  for(size_t i = size; i > 0;){ i--;
    // loop body
  }

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Put the "--" in the condition. It's less ugly.

Pedantically, that doesn't properly invert post-increment in the loop step. It decrements one extra time. If I need to use the loop index after the loop, then decrementing in the condition would cause problems.

  size_t i = size;
  while(i-- > 0){
    // loop body, possibly break
  }
  use(i); // i wraps below 0

  size_t i = size;
  while(i > 0){
    i--;
    // loop body, possibly break
  }
  use(i); // i doesn't wrap

Practically, i leaves the for-loop scope, so most never encounter this problem.

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