gistfile1.txt

sub processor($in) {
    supply {
        whenever $in {
            die "oh no";
        }
    }
}

sub refuses() {
    my $fake-in = Supplier.new;
    processor($fake-in.Supply).tap:
        -> $request {
            die "oops 1";
        },
        quit => -> $exception {
            say "ok";
            return;
        };
    $fake-in.emit("XXX");
    die "oops 2";
}

for ^200 {
    refuses;
}