Finding items that appear only one time in a Javascript array

Question

I\'m trying to find the items that appear only one time in a Javascript array. In the following array:

[\'txfa2\',\'txfa9\',\'txfa2\',\'txfa1\',\'txfa3\',\'t         


        

Answer 1

A concise way to do it:

function singles(array) {
  for (var index = 0, single = []; index < array.length; index++) {
    if (array.indexOf(array[index], array.indexOf(array[index]) + 1) == -1)
      single.push(array[index]);
  };
  return single;
};

var items = ['txfa2', 'txfa9', 'txfa2', 'txfa1', 'txfa3', 'txfa4', 'txfa8', 'txfa9', 'txfa2', 'txfa8'];

console.log(singles( items ))

Demo: http://jsfiddle.net/ThinkingStiff/C849F/

Here's the performance of the non-duplicate answers to this question (that actually work) showing this method (blue) is comparable with the other methods.

Performance: http://jsperf.com/find-array-singles/3