How about something like this:

$SIG{INT} = sub { die "Skip" }

LOOP: for $item (@BigList) {
     eval {
          print "Slowly processing $item..."; 
          # ...
     };

     if ($@ eq 'Skip') {
          # The user pressed ^C
          # If you need to clean up after it, do it here
          # Otherwise, this is a no-op
     }
     elsif ($@) {
          # Something else died
          # You may need some cleanup code here too.
     }
     else {
          # This item was processed w/o any interruptions.
     }
}

So, the concept here is you have wrapped your code in an eval block. If anything dies, it will stop the execution of the eval block at that spot. Outside of the eval block, you can inspect $@ to see if anything died (and what was thrown).

So far, the above is just common exception handling. What we do is setup SIGINT to die with a special message. The equivalent in Java might be throwing a Thread Interrupted Exception.

Please note that eval {} is not the same as eval "" and does not have the associated performance penalty.

Hope this helps.

Ted

In reply to Re: User interactivity in long loops by Anonymous Monk
in thread User interactivity in long loops by Solo

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