[Ns-developers] About TracedCallback signatures

[Timo Bingmann]

Hi guys,

in one of my current wifiex patches I am going to add a new parameter 
RxErrorReason to some of the Wifi traces to indicate the reason for a packet 
drop.

However, with the current system, by adding one TraceSource parameter I break 
all my own old experiments in a very bad way: they don't through compile 
errors, but only show the fault when run. Assuming I am not the only person 
writing experiments with these TraceSources, I also break a lot of other 
people's work. Furthermore, fixing up the callback signatures is exasperatingly 
delicate work.

What are your thoughts on possible remedies to this problem?

- It is probably not possible to do compile-time type checking here. But that 
would need investigation.

- use of a class WifiTraceInformationStruct should be encouraged to keep 
signatures invariant. Of course, also for non-wifi things.

Ideas?
Timo