Defined conditions

A defined condition expression tests whether a compilation variable is defined.

Format

Read syntax diagramSkip visual syntax diagramcompilation-variable-name-1ISNOTDEFINED
compilation-variable-name-1
Must not be the same as a conditional compiler directive keyword.
IS DEFINED
A defined condition that uses the IS DEFINED syntax evaluates to TRUE if the compilation-variable-name-1 is defined.

If a defined condition references a compilation variable that was defined via a DEFINE compiler option, but preceding the defined condition in the program there is neither a corresponding DEFINE directive with the AS PARAMETER phrase nor a DEFINE directive without the OFF phrase for the compilation variable, then the defined condition for the compilation variable evaluates to FALSE.

IS NOT DEFINED
A defined condition that uses the IS NOT DEFINED syntax evaluates to TRUE if the compilation-variable-name-1 is not defined.

A compilation variable whose most recent definition is via a DEFINE directive with the OFF phrase is considered to be not defined.

Related references  
Predefined compilation variables  
DEFINE (Enterprise COBOL Programming Guide)