these operations should have:
- a parameter that tells it to turn on or off sign inclusion.
- a parameter that specifies the number of bits (maybe this can be rounded into bytes) - it should be checked to see if the sign bit fits in with the number of digit bits to make a whole word width.
- a big integer number, signed or unsigned, no floating point I should think, but if you want to handle that, that's up to you.
- integer, the number of bits to shift right or left.

I suggest names like shl, shr, ror, rol OR shiftleft, shiftright, rotateleft, rotateright.