title: How to join an array of strings without using .join()?
body: <p>We're trying to write a function that takes an array of strings and a separator, and joins all the strings separated by such separator.</p>
  
  <p>We are not allowed to use the .join() method.</p>
  
  <p>So far, I'm stuck trying to iterate though all the strings adding a separator between them each time.</p>
  
  <p>I tried something like:</p>
  
  <pre><code>var aName = ['Frank','Vincent','Zappa'];
  
  
  var join = (arr, separator = " ") =&gt; {
      for(var i = 0; i &lt; arr.length; i++) {
          return arr[i] + separator + arr[i+1];
      }
  };
  
  join(aName, ' '); 
  
  //output: "Frank Vincent"
  //expected output: "Frank Vincent Zappa"
  </code></pre>
  
  <p>Thanks for your help.</p>