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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 free variables, the call to xor/3 is delayed until these variables are instantiated.

Fail Conditions

Fails if the result of the evaluation does not unify with Result.

Resatisfiable

No

Exceptions

(4) instantiation fault
Number1 or Number2 is not instantiated (non-coroutining mode only).
(5) type error
Result is a number but not an integer.
(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.
(24) number expected
Result is neither a number nor a variable.

Examples

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

See Also

is / 2