Using a closure:

  function foo(s) {
    function generator(i) {
      return function () {
        return i;
      };
    }

    var r = new Array(s);
    
    for (var i = 0; i < s; i++) {
      r[i] = generator(i);
    }
    
    return r;
  }

  console.log(foo(1000)[42]());

Using Function.prototype.bind():

  function foo(s) {
    function generator(i) {
      return i;
    }

    var r = new Array(s);
    
    for (var i = 0; i < s; i++) {
      r[i] = generator.bind(window, i);
    }
    
    return r;
  }

  console.log(foo(1000)[42]());