The $IF and $SET directives allow for partial compilation of a source file based on the states of software switches. Ten software switches (0 through 9) can be independently changed between binary states ("on" or "off") using the $SET directive. Sections of the source program can then be processed or skipped, depending on the state of any one or a combination of switches used in the $IF directive.
The $IF and $SET directives can be specified on the command line used to invoke the compiler. When specified in that way, the directive must be preceded with a hyphen ("-"). For example:
:ccbl "-Cp -$SET X0=ON HELLOCBL"