...
my $content;
my $response = $ua->get('http://search.cpan.org/');
 
if ($response->is_success) {
    $content = $response->decoded_content;  # or whatever
}
else {
    warn $response->status_line;
}
...

##</code><code>##

use threads;
...
my $content;
my $thread = async{
    my $response = $ua->get('http://search.cpan.org/');
 
    if ($response->is_success) {
        return $response->decoded_content;  # or whatever
    }
    else {
        return undef;
    }
};
...

if( $thread->is_joinable() ) {
    $content = $thread->join;
    if( $content ) {
        #do domething with it
    }
    else {
        # notify the failure?
    }
}