Failing on event occurence

Hello,

I need some help on the following issue. I have a piece of code like:

start:-
  set_event_handler(too_long, stop_execution/0),
  event_after(too_long, 100),
  compute,
  cancel_after_event(too_long).

where "compute" is a predicate that may take a long time to execute. So I
use an event that is triggered 100 secs after the invokation of "compute"
and the predicate "stop_execution" is called.

Now the problem is this: How do I define "stop_execution" and what other
changes might be needed, in order to make the computation behave as if
"compute" failed? I do not need the whole execution to be terminated, I
just need the program to "act as if" the "compute" predicate naturally
failed and backtrack.

Thanks for any suggestions,
Loizos Michael



_________________________________________
Loizos Michael (gemichael@cytanet.com.cy)