BTW, I'm using NaN boxing, and it's great--I can fit a float64 into 8 bytes and have bits left over for tagging pointers, ints, etc. Basically, the idea is to

BTW, I'm using NaN boxing, and it's great--I can fit a float64 into 8 bytes and have bits left over for tagging pointers, ints, etc. Basically, the idea is to encode all non-float values into the NaN representation. The NaN value in a float64 leaves 52-bits undefined. You can use those to encode the other values.