title: Custom regular expression pattern
body: <p>What's the right pattern to obtain something like that using preg_split.</p>
  
  <p>Input:</p>
  
  <pre>
  Src.[VALUE1] + abs(Src.[VALUE2])
  </pre>
  
  <p>Output:</p>
  
  <pre><code>Array ( 
      [0] =&gt; Src.[VALUE1] 
      [1] =&gt; Src.[VALUE2]
  ) 
  </code></pre>