COBOL Manual for TNS/E Programs (H06.03+)

Procedure Division
HP COBOL Manual for TNS/E Programs—520347-003
8-54
Simple Conditions
Simple Conditions
A simple condition has a truth value of TRUE or FALSE. Enclosing a simple condition
within parentheses does not affect its truth value. The simple conditions are:
•
Relation Conditions in General
•
Relation Conditions With Nonpointer Operands
•
Relation Conditions With Pointer Operands
•
Class Conditions
•
Condition-Name Conditions (Conditional Variables)
•
Switch-Status Conditions
•
Sign Conditions
Relation Conditions in General
A relation condition causes a comparison of two operands. The relation condition has a
truth value of TRUE if the relation exists between the operands; otherwise, it has a
truth value of FALSE.
Usage Considerations:
•
Terminology
In the preceding syntax diagrams, the left-hand operand is called the subject of the
condition; the right-hand operand is called the object of the condition.
•
Where Pointer Relations Are Allowed
A relation with pointer operands is allowed in EVALUATE, IF, PERFORM, and
SEARCH VARYING statements. It is not allowed in SEARCH ALL statements,
because pointer data items have no meaningful order.
•
Cannot Compare Literal With Literal
At least one nonpointer operand must be an index-name, identifier, or arithmetic
expression containing at least one reference to a data item; that is, the relation
must include at least one nonliteral element.