JavaScript - run once without booleans

Question

Is there a way to run a piece of JavaScript code only ONCE, without using boolean flag variables to remember whether it has already been ran or not?

Spe

Answer 1

In addition, the nature of what happens in the "/* do stuff here */" may leave something around that, when present, must mean that the function has run e.g.

var counter = null;

function initCounter() {
  if (counter === null) {
    counter = 0;
  }
}