const doStuff = () => {
  alert(`done`);
};
const res1 = (a) => console.log(a, "done");
const res2 = (b) => console.log(b, "dont ever think");

const once = (fn1, fn2) => {
  let done = false;
  return (...args) => {
    if (!done) {
      fn1(...args);
      done = true;
    } else {
      fn2(...args);
    }
  };
};

const doStuffOnce = once(doStuff, res2);
const resOnce = once(res1, res2);