p6.p6

# use Benchy;
use nqp;
use MONKEY-TYPING;

augment class Int {
    method log10_new {
      nqp::if(
        nqp::islt_I(self, 10**300),
        nqp::div_n(nqp::log_n(
          nqp::tonum_I(nqp::decont(self))), nqp::log_n(10e0)),
        nqp::stmts(
          (my num $ans = 0e0),
          (my $leftovers := self),
          nqp::while(
            nqp::isgt_I($leftovers, 10**300),
            ($ans = nqp::add_n($ans,
              nqp::div_n(nqp::log_n(1e300), nqp::log_n(10e0)))),
            $leftovers := nqp::div_I($leftovers, 10**300, Int)),
          nqp::add_n($ans,
            nqp::div_n(nqp::log_n(nqp::tonum_I($leftovers)),
              nqp::log_n(10e0)) )))
    }
}

# my $v = 10**200;
# b 1000_000,
#     { $v.log10 },
#     { $v.log10_new };

say .log10_new for 10, 10**100, 10**99, 10**1000, 10**10000