title: What does the symbol "~" mean in VCL?
body: <p>I am seeing that this is used in <strong>varnish vcl</strong> if statements <strong>"~"</strong></p>
  
  <pre><code>if (req.url ~ "phpMyAdmin") {
      return (pass);
  }
  </code></pre>
  
  <p>I understand that it works like <strong><code>==</code></strong> some time like <strong><code>in_array()</code></strong></p>
  
  <pre><code>if ( req.http.User-Agent ~ "(Android|iPhone|iPad|BlackBerry|SAMSUNG)") 
     return(pass);
  }
  </code></pre>
  
  <p>Can someone please explain what does it actually mean.
  Is it also a default php operator? and what's the difference between it and using <strong><code>==</code></strong></p>