Re: Program unexpectedly terminates

[tobyink]

It would be helpful if the sample code you provided actually compiled (undefined $class, %args and &shuffle prevents compilation with strict subs/vars). Fixing those issues...

#!/usr/bin/env perl
use 5.016;
use warnings;
use Carp::Always;

BEGIN { *CORE::GLOBAL::exit = sub { die("exit called") } }
END { say "END block"; }

my $crawler = Crawler->new;
$crawler->run;

die("finished");

package Crawler {
    use parent 'LWP::UserAgent';
    use List::Util qw(shuffle);

    sub new {
        my ($class, %args) = @_;
        my $self = $class->SUPER::new(%args);
        $self->{ids} = [1..100];
        return $self;
    }

    sub run {
        my $self = shift;
        my @idx = shuffle 0 .. -1 + @{ $self->{ids} };
        my $cur = 0;
        for my $i (@idx) {
            my $id = $self->{ids}[$i];
            printf "%d/%d: %s (%d)\n", ++$cur, 0+@idx, $id, $i;
            # Fetch and process stuff related to this id.
        }
    }

    sub DESTROY { say "Crawler destroyed" }
}

... the code seems to execute correctly here.