Watch a file and chown it once it exists

watch_and_chown.p6

my $PATH = '.';
my $USER = 'muraiki';
my $GROUP = 'staff';

IO::Notification.watch_path($PATH)\
    .unique(:as(*.path), :expires(1))\
    .map(*.path)\
    .grep(* ~~ /\.sock/)\
    .act(-> $socket {
        say "Socket created: $socket";  # actually this happens for any I/O on the file, not just creation
        my $chown_result = run 'chown', "$USER:$GROUP", $socket;
        say $chown_result == 0 ?? "chown $socket succeeded" !! "chown $socket failed: " ~ $chown_result.exitcode;
        exit $chown_result == 0 ?? 0 !! $chown_result.exitcode;                            
    });                                                               
             
sleep;

The weirdness about checking the value of $chown_result is because run is returning an object on failure, which contradicts what's said in https://perl6advent.wordpress.com/2014/12/06/day-06-running-external-programs-from-perl-6/

This is true at least for perl6 version 2015.07.1-151-g5ad8122 built on MoarVM version 2015.07-57-gec051f5