iTS 1.0+)

SCREEN COBOL Source Program

Compaq NonStop™ Pathway/iTS SCREEN COBOL Reference Manual—426750-001

2-22

Complex Conditions

The logical operators must be preceded by a space and followed by a space.

Negated Simple Condition

A simple condition is negated through the use of the logical operator NOT. The negated

simple condition effects the opposite truth value for a simple condition. Parentheses

enclosing negated simple condition do not change the truth value.

Negated simple condition syntax is:

Combined and Negated Combined Conditions

A combined condition results from connecting conditions with AND or OR. Each

condition can be a simple condition, a negated condition, a combined condition or

negated combined condition, or a combination of these.

Combined and negated combined condition syntax is:

Abbreviated Combined Relation Conditions

In a relation where one item is compared to several others, the relation can be

abbreviated by leaving out the subject item name after the first reference to it. If the

relational operator is the same as the previous operator, the operator can also be omitted.

Abbreviated combined relation condition syntax is:

If NOT appears within the abbreviated condition and is not followed by an operator, the

keyword negates that portion of the condition, but does not automatically carry forward

Table 2-9. Logical Operators

AND Logical conjunction—The truth value is true if both conditions are true, and false if

one or both are false.

OR Logical inclusive OR—The truth value is true if one or both of the conditions is

true, and false if both conditions are false.

NOT Logical negation or reversal of truth value—The value is true if the condition is

false and false if the condition is true.

NOT simple-condition

condition { { AND } condition }

{ { OR } }

condition { { AND } [ NOT ] [ operator ] object }...

{ { OR } }