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# xor(+Number1, +Number2, -Result)

Evaluates the bitwise exclusive disjunction Number1 xor Number2 and unifies the resulting value with Result.
Number1
Integer.
Number2
Integer.
Result
A variable or integer.

## Description

This predicate is used by the ECLiPSe compiler to expand evaluable arithmetic expressions. So the call to xor(Number1, Number2, Result) is equivalent to
```    Result is xor(Number1, Number2)
```
which should be preferred for portability.

In coroutining mode, if Number1 or Number2 are uninstantiated, the call to xor/3 is delayed until these variables are instantiated.

### Modes and Determinism

• xor(+, +, -) is det

### Exceptions

(4) instantiation fault
Number1 or Number2 is not instantiated (non-coroutining mode only).
(5) type error
Number1 or Number2 is a number but not an integer.
(24) number expected
Number1 or Number2 is not of a numeric type.

## Examples

```Success:
xor(11, 7, 12).
xor(11, -7, Result).     (gives Result = -14)
Fail:
xor(1, 2, 4).
xor(6, 2, 4.0).
xor(5, 2, r).
Error:
xor(A, 2, 6).              (Error 4).
xor(6, 2.0, 4.0).          (Error 5).
xor(4 + 2, 2, 4).          (Error 24).

```