Even if that's so, modulus (or at least the concept of remainders) are elementary school math and any competent programmer could bang together an (inefficient)

Even if that's so, modulus (or at least the concept of remainders) are elementary school math and any competent programmer could bang together an (inefficient) modulus operator in a few minutes. So even in a language w/o a mod operator, it's not a hard problem if you understand how to solve problems with code.