in reply to Re^3: Ways to control a map() operation
in thread Ways to control a map() operation

Oh yes, you can. But you will not only leave the eval but the loop around it, too. If there is no loop around that eval, you'll die—just like your code demonstrated.

No. You don't leave the eval, you just evaluate a last that will make you leave the loop.

even if the code in my previous post had died in the eval{}, the loop would have continued and the output would have been 123

Of course, but it will not die in the eval, because eval { last; } is like saying last; -- i.e: you're just evaluating the code

eval { bleh(); } is really like saying just bleh(); so your code is simply:

for (1) {
  last;
}

[download]

Otherwise, if it already exits the eval block, why does it exit the loop too?

so just like saying last; outside a loop will die, saying it inside an eval that is outside a loop will die too. It will exit the eval, but just because it died, not because it skipped the block.

--
Leviathan.

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Re^5: Ways to control a map() operation
by betterworld (Curate) on Jul 16, 2006 at 11:56 UTC
    Oh yes, you can. But you will not only leave the eval but the loop around it, too. If there is no loop around that eval, you'll die—just like your code demonstrated.

    No. You don't leave the eval, you just evaluate a last that will make you leave the loop.

    That's what I said, isn't it?
[reply]

      You're playing on words now. The original point is you cannot leave an eval with last. Otherwise this should work:

      
for (1..100) {
    eval {
       if ($_ % 2 == 0) {
           last;
       }
       print $_, "\n";
    };
}

      [download]

      and expect it to print only odd numbers.

      --
      Leviathan.
[reply]
[d/l]
        You're playing on words now. The original point is you cannot leave an eval with last.

        You are right that words are our problem. My original point was that you can leave eval with last. My perception of "leave" is that you stop executing the commands in eval{}. Your perception of leave appears to be to jump right to the end of the eval{} block.

        It's like this: If you step out of your front door, you leave the house. But if you teleport to your friend's, you leave your house, too, don't you.

        In fact, you can "leave" eval{} using die, too.

[reply]

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