Adldap\Schemas\SchemaInterface::true PHP Method

    public function true();

 /**
  * Converts the inserted string boolean to a PHP boolean.
  *
  * @param string $bool
  *
  * @return null|bool
  */
 protected function convertStringToBool($bool)
 {
     $bool = strtoupper($bool);
     if ($bool === strtoupper($this->schema->false())) {
         return false;
     } elseif ($bool === strtoupper($this->schema->true())) {
         return true;
     } else {
         return;
     }
 }