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JavaScript JavaScript Foundations Functions Return Values

Posted by Jason Zoladz
Jason Zoladz
3,013 Points

Error in arrayCounter code challenge

The code check fails if the submitted code doesn't test for undefined, but testing for undefined isn't necessary. That is, you need only return length for an array, else return zero.

index.html 
<!DOCTYPE html>
<html lang="en">
  <head>
    <title>JavaScript Foundations: Functions</title>
    <style>
      html {
        background: #FAFAFA;
        font-family: sans-serif;
      }
    </style>
  </head>
  <body>
    <h1>JavaScript Foundations</h1>
    <h2>Functions: Return Values</h2>
    <script>

      function arrayCounter(arr) {
        if (arr.isArray()) {return arr.length;}
        else {return 0;}
      }

    </script>
  </body>
</html>