test.pl

#!/usr/bin/env perl
use common::sense;
use DDP;
use Mojo::Promise;
use Mojo::IOLoop::Subprocess;

my $subprocess = Mojo::IOLoop::Subprocess->new;
$subprocess->run(
    sub {
        my $subprocess = shift;
        use DDP;

        my $new_ioloop = Mojo::IOLoop->new;

        my @promises;

        for (1 .. 10) {
            my $p = Mojo::Promise->new()->ioloop($new_ioloop);

            $p->then(
                sub {
                    print STDERR "p is running\n\n";

                    $new_ioloop->timer(
                        0.1 => sub {
                            $p->resolve('Lucky!');
                        }
                      )

                }
            )->catch(sub { use DDP; p \@_; });

            push @promises, $p;
        }

        print STDERR "new_ioloop->race\n";

        my $fastest = Mojo::Promise->new()->ioloop($new_ioloop)->race(@promises)->wait();

        print STDERR "not today!\n";

        return $fastest;
    },
    sub {
        use DDP;
        p \@_;
    }
);

$subprocess->ioloop->start unless $subprocess->ioloop->is_running;