[oliverkwebb]

This is also interesting for speed, The algorithms ran by all the impls are identical, but sacrificing speed for cleanliness and adherence to spirit is done regularly.

Without having actually measured, the rust impl probably runs faster than the C impl, but that's not because rust is "faster" than C. That's because I used a closure with one call to floor() for modulus in rust, whilst in C I did 2 fmod()'s to get it because the alternative would've been to make the code unreadable or add a second function/macro (although thinking about it now, undef does exist...)