JavaScript postfix a boolean / one-shot flag for throttling an event

Question

I want to use a flag once, then convert it to false no matter what, after the expression returns the truthiness:

var isProceding = true;
someObject.addEventListener("someEvent", doOnce); // event fires many times

function doOnce () {
    if (isProceding) {
        isProceding = false; // i want to join this line with the previous
        // do stuff
        someObject.removeEventListener("someEvent", doOnce);
    }
}

---

from jsperf

1. if (!isDone++) { 343,020,200 single coercion post fix

2. if (isProceding && isProceding--) { 342,466,581 short circuit post fix

3. if (isProceding) { isProceding = false; 338,360,292 standard

4. if (0 < isProceding--) { 278,447,221 comparison coercion post fix

5. if (isProceding --> false) { 9,983,236 double coercion postfix

Answer 1

Since a number is only falsey at 0

var isDone = 0;

if (!isDone++) {
    // do stuff
}

or

var isProceding = true;

if (isProceding --> false) {
    // do stuff
}