HP SunSoft Pascal 4.0 - Manual (Page 273)

Pascal Preprocessor 249
A
The %debug Directive
The %debug directive instructs pc to compile this line of code when you use
the –cond compiler directive.
Syntax
%debug;
Comments
The %debug directive works in conjunction with the –cond compiler option.
–cond causes pc to compile the lines in your program that begin with
%debug . Without –cond , pc treats lines with %debug as comments.
The output when you define two hostname% pc -xl -config two config.p
hostname% a.out
Begin program.
Two is defined as -32768.
End program.
The output when you define foo hostname% pc -xl -config foo config.p
Fri Mar 3 15:22 1995 config.p
Error: –CONFIG command argument foo was never declared.
Compilation failed