AND, OR, NOT, XOR operators
AND
, OR
, NOT
, XOR
operators that create properties that implement logical operations.
Syntax
expression1 AND expression2
expression1 OR expression2
expression1 XOR expression2
NOT expression1
Parameters
-
expression1, expression2
Expressions whose values will be the operator arguments. Expression values are considered to be
BOOLEAN
class values depending on whether they areNULL
or not.
Examples
likes = DATA BOOLEAN (Person, Person);
likes(Person a, Person b, Person c) = likes(a, b) AND likes(a, c);
outOfInterval1(value, left, right) = value < left OR value > right;
outOfInterval2(value, left, right) = NOT (value >= left AND value <= right);