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    <p>You can use various recursive macro techniques to do things with variadic macros. For example, you can define a <code>NUM_ARGS</code> macro that counts the number of arguments to a variadic macro:</p> <pre><code>#define _NUM_ARGS(X100, X99, X98, X97, X96, X95, X94, X93, X92, X91, X90, X89, X88, X87, X86, X85, X84, X83, X82, X81, X80, X79, X78, X77, X76, X75, X74, X73, X72, X71, X70, X69, X68, X67, X66, X65, X64, X63, X62, X61, X60, X59, X58, X57, X56, X55, X54, X53, X52, X51, X50, X49, X48, X47, X46, X45, X44, X43, X42, X41, X40, X39, X38, X37, X36, X35, X34, X33, X32, X31, X30, X29, X28, X27, X26, X25, X24, X23, X22, X21, X20, X19, X18, X17, X16, X15, X14, X13, X12, X11, X10, X9, X8, X7, X6, X5, X4, X3, X2, X1, N, ...) N #define NUM_ARGS(...) _NUM_ARGS(__VA_ARGS__, 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75, 74, 73, 72, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1) </code></pre> <p>Then with that, you can write a <code>FOREACH</code> macro that expands another macro for each element of a list:</p> <pre><code>#define EXPAND(X) X #define FIRSTARG(X, ...) (X) #define RESTARGS(X, ...) (__VA_ARGS__) #define FOREACH(MACRO, LIST) FOREACH_(NUM_ARGS LIST, MACRO, LIST) #define FOREACH_(N, M, LIST) FOREACH__(N, M, LIST) #define FOREACH__(N, M, LIST) FOREACH_##N(M, LIST) #define FOREACH_1(M, LIST) M LIST #define FOREACH_2(M, LIST) EXPAND(M FIRSTARG LIST) FOREACH_1(M, RESTARGS LIST) #define FOREACH_3(M, LIST) EXPAND(M FIRSTARG LIST) FOREACH_2(M, RESTARGS LIST) : </code></pre> <p>Which will in turn allow you to to define your macro that stringifies each of its arguments:</p> <pre><code>#define STRINGIFY(X) #X #define MY_VARIADIC_MACRO(...) FOREACH(STRINGIFY, (__VA_ARGS__)) </code></pre>
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    1. POIs there a way to use C++ preprocessor stringification on variadic macro arguments?
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    1. USChris Dodd
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    1. COI'm aware of those recursive techniques, but as seen from above they are tedious and they also have the unfortunate restriction that you're limited to the number of args you account for at compile time. I'll update my answer soon with the details of that solution that is not as tedious to implement and is not restricted to a predefined max which is easier to maintain. It might be the best solution for all cases, but for what I need it is a better answer than above. Thanks for the input though!
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