For PHP < 5.3.0, provides access to the getPrevious() method.
string $method The method name:
array $arguments The parameters to be passed to the method:
Exception The previous exception or null
public function __call($method, $arguments) {
if ('getprevious' == strtolower($method)) {
return $this->previous;
}
throw new BadMethodCallException(sprintf('Method "Twig_Error::%s()" does not exist.', $method));
}