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Boolean Operators

Boolean operators perform bit manipulations, Boolean operations, or tests on multiple relations. They return a true (nonzero) or false (zero) value to be used in making a decision.

Syntax

result = expression1 boolean-operator expression2

Comments

boolean-operator is any of the following:

NOT Bit-wise complement
AND Conjunction
OR Disjunction (inclusive ‘or’)
XOR Exclusive ‘or’
EQV Equivalence
IMP Implication

Each operator returns results as indicated in the following truth table. T is true (nonzero) and F is false (zero).

expression1 expression2 NOT AND OR XOR EQV IMP
T T F T T F T T
T F F F T T F F
F T T F T T F T
F F T F F F T T

Boolean operations are performed after arithmetic and relational operations in order of precedence.

Expressions are converted to integers or long integers before a Boolean operation is performed.

If the expressions evaluate to 0 or -1, a Boolean operation returns 0 or -1 as the result. Because Boolean operators do bit-wise calculations, using values other than 0 for false and -1 for true may produce unexpected results.