The $IF statement can be used to "conditionally compile" portions of your source code. In the following example, if the program is compiled with the directives:
/MF /CONSTANT WHERE "PC"
then at compile time, the word "NO" will be displayed and the object code will include an EVALUATE rather than a GO TO statement. If the MF directive were not set, "Not MF dialect" would also be displayed.
$if WHERE = "PC" evaluate test-field when 5 perform test-a end-evaluate $if OTHER-CONSTANT defined $display Program compiled with other-constant set $else $display NO $end $else go to test-a test-b depending on test-field $end $if NOMF set $display Not MF dialect $end