protected function checkPermission($permission)
    {
        $perms = array(
            self::PERMISSION_ALL,
            self::PERMISSION_CHANGE,
            self::PERMISSION_NONE,
            self::PERMISSION_VIEW,
        );
        if (!in_array($permission, $perms)) {
            throw new \InvalidArgumentException(
                'Invalid permission. Must be one of ' . implode(', ', $perms)
            );
        }
    }
protected function checkPermission($permission)
    {
        $perms = array(
            self::PERMISSION_ALL,
            self::PERMISSION_CHANGE,
            self::PERMISSION_NONE,
            self::PERMISSION_VIEW,
        );
        if (!in_array($permission, $perms)) {
            throw new \InvalidArgumentException(
                'Invalid permission. Must be one of ' . implode(', ', $perms)
            );
        }
    }
protected function checkPermission ( $ permission ) { $ perms = array ( self :: PERMISSION_ALL , self :: PERMISSION_CHANGE , self :: PERMISSION_NONE , self :: PERMISSION_VIEW , ) ; if ( ! in_array ( $ permission , $ perms ) ) { throw new \ InvalidArgumentException ( 'Invalid permission. Must be one of ' . implode ( ', ' , $ perms ) ) ; } }
Checks a valid permission.

@param string $permission

@throws \InvalidArgumentException
Checks a valid permission .