ez fibonacci

ezFib.js

function fib() {
  var head = 0;
  var tail = 0;

  return function() {
    var res = head + tail;

    //just for the beginning, so we get 2 rounds with a result of 1
    if (!res) {
      head = 1;
      return head;
    }

    tail = head;
    head = res;
    return res;
  };
}