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    <p>There are a couple of ways to solve the problem. First, you can use typed expression in the macro so you can parse the type. So the <code>CREATE_OBJECT_IMPL</code> would be called like this:</p> <pre><code>CREATE_OBJECT_IMPL(Object, (Arg1) arg1, (Arg2) arg2) </code></pre> <p>Here are some macros that will retrieve the type and strip off the type:</p> <pre><code>#define EAT(x) #define REM(x) x #define STRIP(x) EAT x #define PAIR(x) REM x </code></pre> <p>These macros work like this. When you write <code>STRIP((Arg1) arg1)</code> it will expand to <code>arg1</code>. And when you write <code>PAIR((Arg1) arg1)</code> it will expand to <code>Arg1 arg1</code>. Now next, you will want to do is to apply these macros to each argument that is passed in, so here is a simple <code>APPLY</code> macro that will let you do that for up to 8 arguments:</p> <pre><code>/* This counts the number of args */ #define NARGS_SEQ(_1,_2,_3,_4,_5,_6,_7,_8,N,...) N #define NARGS(...) NARGS_SEQ(__VA_ARGS__, 8, 7, 6, 5, 4, 3, 2, 1) /* This will let macros expand before concating them */ #define PRIMITIVE_CAT(x, y) x ## y #define CAT(x, y) PRIMITIVE_CAT(x, y) /* This will call a macro on each argument passed in */ #define APPLY(macro, ...) CAT(APPLY_, NARGS(__VA_ARGS__))(macro, __VA_ARGS__) #define APPLY_1(m, x1) m(x1) #define APPLY_2(m, x1, x2) m(x1), m(x2) #define APPLY_3(m, x1, x2, x3) m(x1), m(x2), m(x3) #define APPLY_4(m, x1, x2, x3, x4) m(x1), m(x2), m(x3), m(x4) #define APPLY_5(m, x1, x2, x3, x4, x5) m(x1), m(x2), m(x3), m(x4), m(x5) #define APPLY_6(m, x1, x2, x3, x4, x5, x6) m(x1), m(x2), m(x3), m(x4), m(x5), m(x6) #define APPLY_7(m, x1, x2, x3, x4, x5, x6, x7) m(x1), m(x2), m(x3), m(x4), m(x5), m(x6), m(x7) #define APPLY_8(m, x1, x2, x3, x4, x5, x6, x7, x8) m(x1), m(x2), m(x3), m(x4), m(x5), m(x6), m(x7), m(x8) </code></pre> <p>Then you can define the <code>CREATE_OBJECT_IMPL</code> like this:</p> <pre><code>#define CREATE_OBJECT_IMPL(ObjectType, ...) \ ObjectType* Create##ObjectType(APPLY(PAIR, __VA_ARGS__)) \ { \ ObjectType* object = new ObjectType(); \ [...] \ object-&gt;Init(this, APPLY(STRIP, __VA_ARGS__)); \ [...] \ return object; \ } </code></pre> <p>Of course, you might need some workarounds for these macros, if you use them on visual studio. Of course, a better solution is to write a templated function. So you would call your <code>CreateObject</code> like this:</p> <pre><code>ObjectType* obj = CreateObject&lt;ObjectType&gt;(arg1, arg2, arg3); </code></pre> <p>In C++11, you can use varidiac templates like this:</p> <pre><code>template&lt; typename ObjectType, typename... Args &gt; ObjectType* CreateObject(Args... args) { ObjectType* object = new ObjectType(); [...] object-&gt;Init(this, args...); [...] return object; } </code></pre> <p>But if your compiler doesn't support varidiac templates, you can use the <a href="http://www.boost.org/doc/libs/1_54_0/libs/preprocessor/doc/index.html">Boost.PP</a> to generate overloads for up to 10 arguments(or more if you need to):</p> <pre><code>#define GENERATE_OBJS_EACH(z, n, data) \ template&lt;class ObjectType, BOOST_PP_ENUM_PARAMS_Z(z, n, class Arg)&gt; \ ObjectType* CreateObject(BOOST_PP_ENUM_BINARY_PARAMS_Z(z, n, Arg, arg)) \ { \ ObjectType* object = new ObjectType(); \ [...] \ object-&gt;Init(this, BOOST_PP_ENUM_PARAMS_Z(z, n, arg)); \ [...] \ return object; \ } /* Generate CreateObject template for up to 10 arguments */ BOOST_PP_REPEAT_FROM_TO_1(1, 10, GENERATE_OBJS_EACH, ~) </code></pre> <p>Edit: Heres are the workarounds you would need to get the above macros to work in msvc:</p> <pre><code>/* This counts the number of args */ #define NARGS_SEQ(_1,_2,_3,_4,_5,_6,_7,_8,N,...) N #define NARGS_MSVC_WORKAROUND(x) NARGS_SEQ x #define NARGS(...) NARGS_MSVC_WORKAROUND((__VA_ARGS__, 8, 7, 6, 5, 4, 3, 2, 1)) /* This will let macros expand before concating them */ #define PRIMITIVE_CAT(x, y) x ## y #define CAT_MSVC_WORKAROUND(x) PRIMITIVE_CAT x #define CAT(x, y) CAT_MSVC_WORKAROUND((x, y)) /* This will call a macro on each argument passed in */ #define APPLY(macro, ...) APPLY_MSVC_WORKAROUND(CAT(APPLY_, NARGS(__VA_ARGS__)), (macro, __VA_ARGS__)) #define APPLY_MSVC_WORKAROUND(m, x) m x ... </code></pre>
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    1. COThank you very much for your detailed answer. Sadly, I cannot use either variadic templates nor Boost in my context. Your first solution works fine under GCC, but apparently Visual Studio doesn't expand __VA_ARGS__ in the same way, resulting in a serie of syntax errors when I use that solution with more than 1 parameter (cf. [link](http://stackoverflow.com/questions/2575864/the-problem-about-different-treatment-to-va-args-when-using-vs-2008-and-gcc) ). I am currently trying to adapt your solution with the workaround mentionned in that post, but have been unsuccessful so far.
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    2. CO@user2683028 I updated the answer to show the workarounds needed for visual studio.
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    3. COThanks, I also found a workaround using the other post's solution : `#define EXPLICIT(...) __VA_ARGS__` and using it around NARGS and CAT.
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