title: Replace Text label before or after input tag
body: <p>In HTML I have some input tags with labels:</p>
  
  <pre><code>&lt;label&gt;Address &lt;input type="text" name="address" /&gt;&lt;/label&gt;
  &lt;label&gt;&lt;input type="text" name="surname" /&gt; Surname&lt;/label&gt;
  </code></pre>
  
  <p>I want to change labels text with a javascript funcion.<br>
  I know it's possible eg. with</p>
  
  <pre><code>input_name.parentNode.firstChild.nodeValue = "New label text";
  </code></pre>
  
  <p>Unfortunatly labels are both before and after input. So firstChild as well as lastChild.</p>
  
  <p>I know it's possible to put labels into <code>&lt;span&gt;</code> and use getElementById.  But I prefer not.<br>
  Maybe it's also possible adding <code>id</code> or <code>for</code> to the label...  But I prefer not.</p>
  
  <p>How can I easly replace the "first TextNode sibling before or after input"?</p>