_getRuleType example

if (null === $privilege) {
            // query on all privileges             do {
                // depth-first search on $role if it is not 'allRoles' pseudo-parent                 if (null !== $role && null !== ($result = $this->_roleDFSAllPrivileges($role, $resource, $privilege))) {
                    return $result;
                }

                // look for rule on 'allRoles' psuedo-parent                 if (null !== ($rules = $this->_getRules($resource, null))) {
                    foreach ($rules['byPrivilegeId'] as $privilege => $rule) {
                        if (self::TYPE_DENY === ($ruleTypeOnePrivilege = $this->_getRuleType($resource, null, $privilege))) {
                            return false;
                        }
                    }
                    if (null !== ($ruleTypeAllPrivileges = $this->_getRuleType($resource, null, null))) {
                        return self::TYPE_ALLOW === $ruleTypeAllPrivileges;
                    }
                }

                // try next Resource                 $resource = $this->_resources[$resource->getResourceId()]['parent'];

            }