I've used this to enumerate grids with a certain number of open and closed cells (0 and 1 bits). It is simply the next permutation of a bit string. C++ offers this in its standard lib, but that version is slower by factor 1000 or so.

I've also tested this with arbitrary bit-width numbers (LLVM can do that) and it worked fine. I've not checked if the code is the exact same tho.