# Node list iteration

## JavaScript performance comparison

Test case created

## Info

Comparing two different styles of iterating through node lists.

## Preparation code

``<div class="ancestor">  <div class="interesting">1</div>  <div class="not-interesting"></div>  <div class="interesting">2</div>  <div class="also-not-interesting"></div>  <div class="interesting">3</div>  <div class="interesting">4</div>  <div class="also-not-interesting"></div>  <div class="also-not-interesting"></div>  <div class="container">    <div class="not-interesting"></div>     <div class="interesting">5</div>     <div class="interesting">6</div>     <div class="also-not-interesting"></div>     <div class="subcontainer">       <div class="interesting">7</div>       <div class="also-not-interesting"></div>       <div class="interesting">8</div>     </div>   </div> <script>  Benchmark.prototype.setup = function() {    var ancestor = document.querySelector('.ancestor');    var interestingNodes = ancestor.querySelectorAll('.interesting');    var result = [];  };</script>``

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## Test runner

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Testing in unknown unknown
Test Ops/sec
Length iteration
``for (var i = 0; i < interestingNodes.length; i++) {  var interestingNode = interestingNodes[i];  result.push(interestingNode);}``
pending…
Truthy iteration
``for (var i = 0, interestingNode; interestingNode = interestingNodes[i]; i++) {  result.push(interestingNode);}``
pending…
Cached length iteration
``var len = interestingNodes.length;for (var i = 0; i < len; i++) {  var interestingNode = interestingNodes[i];  result.push(interestingNode);}``
pending…

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