I have some complicated code that is getting an exception deep inside an eval (specifically "Can't use an undefined value as a symbol reference"). This happens about 1 in every 100,000 transactions, from one of several dozen possible code paths. Without a stack trace I'm pretty stuck.

Is there a way to get caller() information through eval, at the eval level? I know (example below) how to print it locally from a method. But if I don't know in advance where the problem will come from, can I get a stack trace later, bubbled up to the eval?

Note that Carp, I think, won't work, since the exception is caused by a perl error, not an explicit die/carp/cluck. 

eval {
        level2();
};
if($@) {
        print "Error $@";
        #want to print stack trace HERE!
}

sub level2
{
        print "This is level2\n";
        level3();
}

sub level3
{
        print "This is level3\n";

        $i = 0;
        while(($package, $filename, $line, $subroutine)=caller($i++)) 
+{
                print "caller($i)=$package, $filename, $line, $subrout
+ine\n";
                }

        $zero = 0;
        $zero = 100 / $zero;
}

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Other monks postings on similar topics include http://www.perlmonks.org/?node_id=226358 and http://www.perlmonks.org/?node_id=211954

In reply to Capturing stack trace in eval by brycen

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