title: Detect opening and closing brackets
body: <p>From a string:</p>
  
  <pre><code>"(book(1:3000))"
  </code></pre>
  
  <p>I need to exclude opening and closing brackets and match:</p>
  
  <pre><code>"book(1:3000)"
  </code></pre>
  
  <p>using regular expression.</p>
  
  <p>I tried this regular expression:</p>
  
  <pre><code>/([^',()]+)|'([^']*)'/
  </code></pre>
  
  <p>which detects all characters and integers excluding brackets. The string detected by this regex is:</p>
  
  <pre><code>"book 1:3000"
  </code></pre>
  
  <p>Is there any regex that disregards the opening and closing brackets, and gives the entire string?</p>