Controlling compiler directive in file from other file C++ - c++

Question

Consider following header file,
// filename : packet_types.h
#ifndef _PACKET_TYPES_
#define _PACKET_TYPES_
struct Packet {
enum Type {
typ_ONE,
typ_TWO,
typ_THREE,
};
static const char * STRINGS[] = {
"ONE",
"TWO",
"THREE"
};
const char * getText( int enum ) {
return STRINGS[enum];
}
};
#endif
As Arduino has limited memory, I don't want to include this portion of code when I include this file, packet_types.h,
static const char * STRINGS[] = {
"ONE",
"TWO",
"THREE"
};
const char * getText( int enum ) {
return STRINGS[enum];
}
But for my GUI application, I want the complete file. I want to use same file for both Arduino and GUI, but how can I add compiler directive #define,#ifdef, #ifndef... to do this job, when I include this file from some other file(main.cpp). Thanks.

Answer 1

Although it is possible to use some preprocessor juggling, the right solution is to simply use C++ as it was intended to be used. Only declare these class members and methods in the header file:
static const char * STRINGS[];
const char * getText( int enum );
And then define them in one of the source files:
const char * Packet::STRINGS[] = {
"ONE",
"TWO",
"THREE"
};
const char * Packet::getText( int enum ) {
return STRINGS[enum];
}
With the aforementioned preprocessor juggling, all it ends up accomplishing is the same logical result, but in a more confusing and roundabout way.