public function check_authorizations(Category $category)
 {
     $nbr_bits = count($this->authorizations_bits);
     if ($nbr_bits == 0) {
         return true;
     } else {
         $authorized_bits = array();
         foreach ($this->authorizations_bits as $bit) {
             if ($this->allow_only_member_level_authorizations && Authorizations::check_auth(RANK_TYPE, User::MEMBER_LEVEL, $category->get_authorizations(), $bit) || $category->check_auth($bit)) {
                 $authorized_bits[] = $bit;
             }
         }
         $nbr_authorized_bits = count($authorized_bits);
         if ($this->check_all_bits) {
             return $nbr_authorized_bits == $nbr_bits;
         } else {
             return $nbr_authorized_bits >= 1;
         }
     }
 }