# Perl replica of Aborting a Barrier
# https://superfastpython.com/multiprocessing-barrier-in-python/

use MCE::Simple -strict, -signatures;
use MCE::Barrier;
use Time::HiRes 'sleep';
use Try::Tiny;

STDOUT->autoflush(1);

sub task ($barrier, $number) {
    # generate a unique value and block for a moment
    my $value = rand() * 10; sleep($value);

    # report result
    say "Process ${number} done, got: ${value}";

    # check if the result was "bad"
    if ($value > 8) {
        say "Process ${number} aborting...";
        $barrier->abort;
    }
    else {
        # wait on all other processes to complete
        # my ($remaining, $error) = $barrier->wait;
        # or via exception handling
        try {
            $barrier->wait;
        }
        catch {
            # pass
        };
    }
}

sub main () {
    # create a barrier plus one for the main process
    my $barrier = MCE::Barrier->new(5 + 1);

    # create the worker processes
    spawn task($barrier, $_) for 1..5;

    # wait for all processes to finish
    # my ($remaining, $error) = $barrier->wait;
    # or via exception handling
    try {
        $barrier->wait();
        say "All processes have their result";
    }
    catch {
        # $_ = "Barrier aborted ..."
        say "At least one process aborted due to bad results";
    };

    # reap the worker processes
    sync;
}

main();

__END__
Process 1 done, got: 1.12563261603103
Process 5 done, got: 1.89097026203857
Process 4 done, got: 4.19963585053669
Process 3 done, got: 6.5083014390348
Process 2 done, got: 8.81696702753292
Process 2 aborting...
At least one process aborted due to bad results