variable num

var_num.h

#define VA_NUM_ARGS(...) VA_NUM_ARGS_IMPL(__VA_ARGS__, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1)
#define VA_NUM_ARGS_IMPL(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, N, ...) N

#define MACRO_DISPATCHER(func, ...) MACRO_DISPATCHER_(func, VA_NUM_ARGS(__VA_ARGS__))
#define MACRO_DISPATCHER_(func, nargs) MACRO_DISPATCHER__(func, nargs)
#define MACRO_DISPATCHER__(func, nargs) func ## nargs

#define VAR1(x)       L ## #x" = " << x
#define VAR2(x, ...)  L ## #x" = " << x << L", " << VAR1(__VA_ARGS__)
#define VAR3(x, ...)  L ## #x" = " << x << L", " << VAR2(__VA_ARGS__)
#define VAR4(x, ...)  L ## #x" = " << x << L", " << VAR3(__VA_ARGS__)
#define VAR5(x, ...)  L ## #x" = " << x << L", " << VAR4(__VA_ARGS__)
#define VAR6(x, ...)  L ## #x" = " << x << L", " << VAR5(__VA_ARGS__)
#define VAR7(x, ...)  L ## #x" = " << x << L", " << VAR6(__VA_ARGS__)
#define VAR8(x, ...)  L ## #x" = " << x << L", " << VAR7(__VA_ARGS__)
#define VAR9(x, ...)  L ## #x" = " << x << L", " << VAR8(__VA_ARGS__)
#define VAR10(x, ...) L ## #x" = " << x << L", " << VAR9(__VA_ARGS__)
#define VAR11(x, ...) L ## #x" = " << x << L", " << VAR10(__VA_ARGS__)
#define VAR12(x, ...) L ## #x" = " << x << L", " << VAR11(__VA_ARGS__)
#define VAR13(x, ...) L ## #x" = " << x << L", " << VAR12(__VA_ARGS__)
#define VAR14(x, ...) L ## #x" = " << x << L", " << VAR13(__VA_ARGS__)
#define VAR15(x, ...) L ## #x" = " << x << L", " << VAR14(__VA_ARGS__)
#define VAR16(x, ...) L ## #x" = " << x << L", " << VAR15(__VA_ARGS__)

#define VAR(...) MACRO_DISPATCHER(VAR, __VA_ARGS__) (__VA_ARGS__)

#include <string>
#include <iostream>

using namespace std;

int main()
{
  char str[] = "hello world";
  int val = 42;
  double val_d = 3.14;
  bool val_b = true;
  wcout << VAR(str, val, val_d, val_b) << endl;
}