title: How to append a dot at the beginning of a string in array-Javascript
body: <p>I have an array:</p>
  
  <pre><code>arr= ["abd","test","testss"];
  </code></pre>
  
  <p>I want to add dot in front of all the strings like:</p>
  
  <pre><code>arr= [".abd",".test",".testss"];
  </code></pre>
  
  <p>this failed:</p>
  
  <pre><code>arr.forEach(function(e){
    e.append(".")
  })
  </code></pre>
  
  <p>how can I do this?</p>