JavaScript closure of iterator index

js-closure-iterator-index

var foos = [
  { bar: 1 },
  { bar: 2 }
];

for (var i = 0; i < foos.length; i++) (function(index) {
  setTimeout(function() {
    console.log(foos[index].bar);
  }, 1);
})(i);

// rather than

for (var j = 0; j < foos.length; j++) {
  setTimeout(function() {
    console.log(foos[j].bar);
  }, 1);
}