int main(){
    // exception, information hiding 
    array(int) arr = ({2,2,2,2});
    mixed error = catch {
            int i = arr[sizeof(arr)]; // nullatol indexel 
    };
    if(error == 0){
            write("OK\n");
    }else{
        write("nagyon nem ok\n");
        write(error->error_type());
        write(error->describe());
    }
}