Hi,

For safety use, it's better to have null check for all variables which are used in this function.

if (!_sessionPriv.$clientAlarmList) {
    return;
}

↓

if (!_sessionPriv.$clientAlarmList
     || !_sessionPriv.$monitoredItemForAlarmList
     || !_sessionPriv.$subscriptionforAlarmList ) {
    return;
}

https://github.com/node-opcua/node-opcua/blob/master/pack

Is this a bug or feature request?

FR

What is the current behavior?

not in the tree

What is the expected or desired behavior?

should be under the section "System"