ifdef Statement--Process a Set of Statements with Variables or Logicals
Processes a set of statements depending on whether a $variable or $$logical is defined. The statements within the ifdef-endif block are executed only if the $$logical or $variable has been defined. The statements are executed even if the $variable is created with no value.
The statements in the optional else clause are executed if the $$logical or $variable is not defined.
This statement has the following syntax:
## ifdef $variable | $$logical {statement}
[## else {statement}]
## endif
Example--ifdef statement:
The following statements generate a 4GL comment stating the value of II_TFDIR, if it is defined:
## IFDEF $$II_TFDIR
/* II_TFDIR: $$II_TFDIR */
## ENDIF