title: Why doesn't `\d` work in regular expressions in sed?
body: <p>I am trying to use <code>\d</code> in regex in sed but it doesn't work:</p>
  
  <pre><code>sed -re 's/\d+//g'
  </code></pre>
  
  <p>But this is working:</p>
  
  <pre><code>sed -re 's/[0-9]+//g'
  </code></pre>