perl doesn't have hexadecimal numbers. Or decimal numbers. Or octal numbers. You may refer to integer values in Perl code using hexadecimal, decimal, octal or binary, but internally, they're all the same.

Could you explain what you mean by "hexadecimal numbers"? Considering that Exclusive-OR operates on truth values (or bits), how do you intend to apply this on "hexadecimal numbers"?