如何在Main.cpp中声明的全局变量可以在头文件中访问

Question

How would I get a global variable to appear in a header that's included after the variable's declaration? I have it arranged like this, but within the header, it's not recognized as being defined:

main.cpp:

const int COUNT = 10;
void (* FUNCTION[COUNT])();
const char * DESCRIPTION[COUNT];

#include "TestFont.h"

testFont.h:

#define COUNTER_VAR = __COUNTER__;
DESCRIPTION[COUNTER_VAR] = "description";
FUNCTION[COUNTER_VAR] = func;
#undef COUNTER_VAR

In the header, DESCRIPTION and FUNCTION are seen as undefined, how would I make it so they can be used?

Disclaimer: It's super ugly isn't it! This is strictly for a sandbox project in VS, so I can write small single-file tests or scripts in C++ with as little IDE setup ceremony as possible. The goal is to make it so all I need do is include the header in main.cpp, and main will have the necessary function pointer and description to list it as an option in the console. No grades please!

Answer 1

The following lines are not legal outside of a function body.

DESCRIPTION[COUNTER_VAR] = "description";
FUNCTION[COUNTER_VAR] = func;

You may need to wrap that in a helper function.

static int init()
{
#define COUNTER_VAR = __COUNTER__;
   DESCRIPTION[COUNTER_VAR] = "description";
   FUNCTION[COUNTER_VAR] = func;
#undef COUNTER_VAR
}

and call the function.

static int dummy = init();