MWScript doesn't have a bitwise XOR function, but it does have an AND with ones-complement function in ClearFlag, which provides a bitwise NOT, which can be used with TestFlags (which is bitwise AND) to do a NAND. Thus you can use these to implement a 32-bit XOR.
on NAND(a, b) return ClearFlag(#FFFFFFFF, TestFlags(a, b)) end on XOR(a, b) return NAND(NAND(a, NAND(a, b)), NAND(b, NAND(a, b))) end on Load let x = xor(#FFFF00FF, #8000FF55) syslog(NumToText(x, NumFormHex32)) end