gistfile1.txt

{
    Include: test.h

    Include: test2.h

    Unknown: {
something
    }

    Condition: 1 + 1 == 2 {
    }

    Unknown: {
woot
    }

    End condition

    Condition: defined _WIN32 {
    }

    Unknown: {
is windows
    }

    Else condition: defined __unix__ {
    }

    Unknown: {
is unix
    }

    End condition

    Define variable: PI {
3.14159
    }

    Undefine: PI

    Define function: RADTODEG(x) {
((x) * 57.29578)
    }

}

main.d

module main;
import defs;
import parser;
import std.stdio;

void main() {
	PPFile file = PPFile("""
#include \"test.h\"
#include <test2.h>
something
#if 1 + 1 == 2
    woot
#endif

#ifdef _WIN32
    is windows
#elif defined __unix__
    is unix
#endif

#define PI 3.14159
#undef PI
#define RADTODEG(x) ((x) * 57.29578)
""");
	executePPParser(file);
	writeln(file.toString());
}