gistfile1.txt

pir::nqp_bigint_setup__v();

my $knowhow := pir::get_knowhow__P();
my $bi_type := $knowhow.HOW.new_type(:name('TestBigInt'), :repr('P6bigint'));
$bi_type.HOW.compose($bi_type);

sub fac_bi($n) {
    my $i := $n;
    my $r := nqp::box_i(1, $bi_type);
    while $i > 1 {
        $r := pir::nqp_bigint_mul__PPP($r, nqp::box_i($i, $bi_type));
        $i := $i - 1;
    }
    $r
}

say(pir::nqp_bigint_to_str__SP(fac_bi(1000)));