Re^5: Why eval {...};if ($@) { die $@ } else { ...???

Well. As you know, the eval BLOCK is good for not dying. The eval BLOCK; die $@ if $@ is good for dying somewhere else, and not inside the code that's in the eval BLOCK. I don't know the specifics of that module you are talking about, but I've provided a simple example which shows the difference, even not adding anything to the argument to die but $@.

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Re^6: Why eval {...};if ($@) { die $@ } else { ...???
by Jenda (Abbot) on Apr 04, 2009 at 00:45 UTC

So if I understand right ... you might want to die somewhere else just in case the $SIG{__DIE__} was set differently? Or maybe so that it's called several times?

use Carp;

$SIG{__DIE__} = sub {print STDERR "handler called\n"};

eval {

    eval {
        confess "blah\n";
    };
    if ($@) {
        die $@;
    }
};
print $@ if $@;
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I don't think I would want that ever. Actually I think $SIG{__DIE__} should be avoided due to the way it's implemented. Let's see what does perlvar say:

Due to an implementation glitch, the $SIG{__DIE__} hook is called even inside an eval(). Do not use this to rewrite a pending exception in $@, or as a bizarre substitute for overriding CORE::GLOBAL::die(). This strange action at a distance may be fixed in a future release so that $SIG{__DIE__} is only called if your program is about to exit, as was the original intent. Any other use is deprecated.

Jenda
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