Nette\Security\Permission::searchRolePrivileges PHP Метод

    private function searchRolePrivileges($all, $role, $resource, $privilege)
    {
        $dfs = ['visited' => [], 'stack' => [$role]];
        while (NULL !== ($role = array_pop($dfs['stack']))) {
            if (isset($dfs['visited'][$role])) {
                continue;
            }
            if ($all) {
                if ($rules = $this->getRules($resource, $role)) {
                    foreach ($rules['byPrivilege'] as $privilege2 => $rule) {
                        if (self::DENY === $this->getRuleType($resource, $role, $privilege2)) {
                            return self::DENY;
                        }
                    }
                    if (NULL !== ($type = $this->getRuleType($resource, $role, NULL))) {
                        return $type;
                    }
                }
            } else {
                if (NULL !== ($type = $this->getRuleType($resource, $role, $privilege))) {
                    return $type;
                } elseif (NULL !== ($type = $this->getRuleType($resource, $role, NULL))) {
                    return $type;
                }
            }
            $dfs['visited'][$role] = TRUE;
            foreach ($this->roles[$role]['parents'] as $roleParent => $foo) {
                $dfs['stack'][] = $roleParent;
            }
        }
        return NULL;
    }