C++ Macro overload, C++ (vc++)

C++ Macro overload

#include <iostream>

// General utility macro
#define PP_CAT( A, B ) A ## B
#define PP_EXPAND(...) __VA_ARGS__

// Macro overloading feature support
#define PP_VA_ARG_SIZE(...) PP_EXPAND(PP_APPLY_ARG_N((PP_ZERO_ARGS_DETECT(__VA_ARGS__), PP_RSEQ_N)))

#define PP_ZERO_ARGS_DETECT(...) PP_EXPAND(PP_ZERO_ARGS_DETECT_PREFIX_ ## __VA_ARGS__ ## _ZERO_ARGS_DETECT_SUFFIX)
#define PP_ZERO_ARGS_DETECT_PREFIX__ZERO_ARGS_DETECT_SUFFIX ,,,,,,,,,,,0

#define PP_APPLY_ARG_N(ARGS) PP_EXPAND(PP_ARG_N ARGS)
#define PP_ARG_N(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, N,...) N
#define PP_RSEQ_N 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0

#define PP_OVERLOAD_SELECT(NAME, NUM) PP_CAT( NAME ## _, NUM)
#define PP_MACRO_OVERLOAD(NAME, ...) PP_OVERLOAD_SELECT(NAME, PP_VA_ARG_SIZE(__VA_ARGS__))(__VA_ARGS__)

// Usage example
#define FOO(...)       PP_MACRO_OVERLOAD(FOO, __VA_ARGS__)
#define FOO_0()        "Zero"
#define FOO_1(X)       "One"
#define FOO_2(X, Y)    "Two"
#define FOO_3(X, Y, Z) "Three"

int main()
{
    std::cout << FOO() << "\n" << 
                 FOO(1) << "\n" << 
                 FOO(1, 2) << "\n" << 
                 FOO(1, 2, 3) << std::endl;
}


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