title: Unable to Match numbers only using Regular Expression in golang using Regex
body: <pre><code>matched, err := regexp.MatchString(`[0-9]`, `a.31`)
  fmt.Println(matched)
  </code></pre>
  
  <p>The above expression is returning true.. Isn't it supposed to be false? </p>
  
  <p>I want to extract only numbers but why is "a.31" considered true? I've noticed that having atleast a number in the string will return "true"... </p>
  
  <p>How to make it return "true" only for numbers?</p>