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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <h1>smart checkbox group</h1>
<div class="row">
<form name="myform" class="two-up">
    <legend>Have you had any of these beers?</legend>
      <input type="checkbox" name="checkboxname[]" value="Franziskaner Hefe-Weisse">Franziskaner Hefe-Weisse
      <input type="checkbox" name="checkboxname[]" value="Revolver Blood And Honey">Revolver Blood And Honey
      <input type="checkbox" name="checkboxname[]" value="Fat Tire">Fat Tire
      <input type="checkbox" name="checkboxname[]" value="St. Bernardus Tripel">St. Bernardus Tripel
      <input type="checkbox" name="checkboxname[]" value="none">none of the above
<div id="output" class="two-up">Nothing Selected</div>

              body {
  font-family: sans-serif;
label {
  margin: 0.618em 0;
  display: block;
#output {
  background: #fafafa;
  margin: 1em 0;
  padding: 1em;

.row {
  display: flex;
  flex-direction: row;
.two-up {
  flex: 1;
              (function ($) {

  // get a collection of only the checked checkboxes.
  var getChecked = function () {
    return $("input[name='checkboxname[]']:checked");

  // extract the values from the checked checkboxes. Returns an array.
  var getValues = function () {
    return getChecked()
    .map(function () {
      return this.value; 

  // handles none of the above unchecking. Takes the initiator element as an arguement.
  var noneOfTheAbove = function (initiator) {
    var checked = getChecked();
    return checked.each(function () {
      var userClickedNone = initiator.value === 'none';
      var currentElIsNone = this.value === 'none';
      // (User clicked "none of the above") XOR (Current Element in the loop is "none of the above")
      // (A implies B) implies (not (B implies A))
      var uncheck = userClickedNone^currentElIsNone;
      if(uncheck) {
        $(this).prop('checked', false);

  // change handler that ouputs the selected values to the screen
  var output = function (e) {
    var initiator = typeof e !== 'undefined' ? e.target : {};
    var arr = getValues();
    var el = $('#output');
    if(arr.length > 0) {
      if(arr.indexOf('none') > -1) {
        // pass the checkbox the user clicked to the noneOfTheAbove method

      // output to screen
    } else {
      // default output if nothing is checked
      el.text('Nothing Selected Yet');

  // register output handler to all thec `checkboxname` checkboxes

  // default output


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