/**
* @return string
*
* @throws BuildException
*/
protected function doSelect()
{
$this->reg->setPattern($this->pattern);
$this->reg->setModifiers($this->modifiers);
$this->reg->setIgnoreCase(!$this->caseSensitive);
$output = $this->defaultValue;
try {
if ($this->reg->matches($this->subject)) {
$output = $this->reg->getGroup((int) ltrim($this->match, '$'));
}
} catch (Exception $e) {
throw new BuildException($e);
}
return $output;
}