Re: Argument passing in Schedule

[Ho-Sheng Hsiao]

On Sun, 9 Feb 1997, glen e. p. ropella wrote:
> > The way I coded my model, I have a two schedules under one ModelSwarm. One
> > is the regular repeating schedule, and the other holds a discrete event
> > "scratch schedule" a la mousetraps.

> How and where did you activate the scratch schedule?  Did you activateIn
> on the modelSwarm (self) or the modelSwarm's activity?

-activateIn: (id) swarmContext {
   [super activateIn: swarmContext];
   [modelSchedule activateIn: self];
   [modelScratchSchedule activateIn: self];
   return getActivity;
}

> > The definition for eventReceiveMessage is
> > 
> > -(int) eventReceiveMessage: (RouterMessage *) msg;

> It looks to me like your selector is fine, at least in argument terms.
> If it's the problem, I would suspect the (int) return value before I
> would suspect the argument.

Actually, I did. I tried it with (void) and (id) -- same results. The NeXT
ObjC manual isn't clear if the return value affects the return value. In
any case, gcc warns of messages returning different return values (as
defined in @interface or @implementation). 

> I would concentrate on checking the time at which you intend to send
> the message and what time getCurrentTime() + 1 is returning.  BTW, in

I did that -- it looks fine. Of course, my only way of knowing that is
approximating the time on the graphs... any way to check for the exact time?

> your code fragment above, your parentheses are not closed around
> getCurrentTime() +1.

Oops. It's there in the original code, though.

> Anyway, you might also put something on the schedule before it's
> activated (so that it is non-zero to begin with) and see if it 
> does that at least once.  

Good idea... let's see: immediatly right after building the actions, I tried
sending the message. It works -- the schedule, the (debug) message).
However, I used a constant time (1) instead of (getCurrentTime() + 1)
since the app aborts... still, *during* the execution, the debug
message won't print out.

> >  1) I added a nil check for both target and modelScratchSchedule. The
> >     modelScratchSchedule wasn't nil, but the target was. So I said to
> >     myself, "maybe this will work". When I fixed that bug, the debug message
> >     still doesn't print out.
> 
> Are you saying that the target is no longer "nil?"  I.e. that a 
> message is, in fact, being sent to a valid object?  

That's right: I fixed the bug that caused target to be nil, but the result
is still the same.


---hhh