title: How to write isNumeric function in Golang?
body: <p>I want to check if a string is numeric. </p>
  
  <p>For example:</p>
  
  <ul>
  <li><code>"abcd123"</code> should return <code>false</code>. </li>
  <li><code>"1.4"</code> or <code>"240"</code> should return <code>true</code>. </li>
  </ul>
  
  <p>I thought about using <code>ParseInt</code> and <code>ParseFloat</code> (from the <code>strconv</code> package), but am not sure if that is the right way.</p>