title: Performance - Array.forEach vs implemented version
body: <p>I would have expected a native version to be faster.</p>
  
  <p>What gives?</p>
  
  <p><a href="http://jsperf.com/native-vs-implmented-0" rel="noreferrer">http://jsperf.com/native-vs-implmented-0</a></p>
  
  <p><strong>Implementation</strong></p>
  
  <pre><code>function each (obj, func, context) {
      var kindex,
          length;
      for (kindex = 0, length = obj.length; kindex &lt; length; kindex++) {
          func.call(context, obj[kindex], kindex, obj);
      }
  }
  </code></pre>
  
  <p><strong>Test Cases</strong></p>
  
  <pre><code>// implemented
  each([0,1,2,3], function(val){
      val++;
  })
  </code></pre>
  
  <p>vs</p>
  
  <pre><code>// native
  [0,1,2,3].forEach(function(val){
      val++
  })
  </code></pre>