Are function arguments stored in a closure?

Posted by Nick Lowman on Stack Overflow See other posts from Stack Overflow or by Nick Lowman
Published on 2010-05-19T13:15:02Z Indexed on 2010/05/19 13:30 UTC
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I was reading this great article about closures here and the example below outputs 'item3 undefined' three times.

I understand why it outputs 'item3' three times as the functions inside buildList() all use the same single closure but why can't it access the 'list' argument? Why is it undefined? Is it because the argument is passed in after the closure has been created?

function buildList(list) {
  var result = [];
  for (var i = 0; i < list.length; i++) {
    var item = 'item' + list[i];
    result.push( function() {console.log(item + ' ' + list[i])} );
  }
  return result;
}

function testList() {
  var fnlist = buildList([1,2,3]);
  // using j only to help prevent confusion - could use i
  for (var j = 0; j < fnlist.length; j++) {
    fnlist[j]();
  }
}

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