/**
* Do we have all the necessary inputs to execute one of the potential response trees?
* @param stack_potentialresponse_tree $prt the tree in question.
* @param array $response the response.
* @param bool $acceptvalid if this is true, then we will grade things even
* if the corresponding inputs are only VALID, and not SCORE.
* @return bool can this PRT be executed for that response.
*/
protected function can_execute_prt(stack_potentialresponse_tree $prt, $response, $acceptvalid)
{
// The only way to find out is to actually try evaluating it. This calls
// has_necessary_prt_inputs, and then does the computation, which ensures
// there are no CAS errors.
$result = $this->get_prt_result($prt->get_name(), $response, $acceptvalid);
return null !== $result->valid && !$result->errors;
}
