gistfile1.txt

my class Node {
    has $.value;
    has $.next;
}
for 1..4 -> $attempt {
    my $head = Node;
    await start {
        for 1..10000 -> $i {
            loop {
                my $orig = $head;
                my $next = Node.new(value => $i, next => $orig);
                last if cas($head, $orig, $next) === $orig;
            }
        }
    } xx 4;

    my $total = 0;
    my $cur = $head;
    while $cur {
        $total += $cur.value;
        $cur = $cur.next;
    }
    say $total == 4 * [+](1..10000);
}