Increment function using closure

closure.js

function makeIncrementer(x) {
  return function() {
    return x++;
  };
}

var increment = makeIncrementer(0);

console.log(increment());  //0
console.log(increment());  //1
console.log(increment());  //2
console.log(increment());  //3
console.log(increment());  //4
console.log(increment());  //5