use strict;
use warnings;

use threads;
use threads::shared;

use Thread::Queue;

my $queue = new Thread::Queue;

sub hello {
    print "Hello\n";
}

sub worker {
    my $tid = threads->self->tid;
    
    print "[$tid] Starting\n";

    while (my $job = $queue->dequeue) {
        print "Got a job\n";
    }

    print "[$tid] Terminating\n";
}


my @tlist;
my $workers = 4;

# Start Workers
for (my $i = 0; $i < $workers; $i++) {
    push(@tlist, threads->new(\&worker));
} 

for (my $i = 0; $i < 10; $i++) {
    $queue->enqueue(\&hello); # This causes my trouble
}

sleep(5);

# Wait for workers to finish
foreach my $w (@tlist) {
    $queue->enqueue(undef);
}

foreach my $w (@tlist) {
    $w->join;
}