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C is a Variadic macro that expands into a set of macrososes for each argument

I want to have one macro call that takes several function pointers, and each function pointer is called by a second macro, which is a function declaration.

I want two macros in the form

#define FUNCTION_DEF(func) extern int func(void);
#define FUNCTION_DEFS(...) (???)

which is called as such

FUNCTION_DEFS(
    myFunc1,
    myFunc2,

    otherFunc1,
    otherFunc2,

    defaultFunc
)

which is expanding into

FUNCTION_DEF(myFunc1)
FUNCTION_DEF(myFunc2)

FUNCTION_DEF(otherFunc1)
FUNCTION_DEF(otherFunc2)

FUNCTION_DEF(defaultFunc)

In other words, this single call FUNCTION_DEFSexpands into function declarations of all variational arguments.

For the time being, I just skipped the first step and typed FUNCTION_DEFa function for each pointer, however, the solution for this would be great.

Is it possible?

Edit:

@Vality X-Macro. " X-Macros ", , .

+4
2

, , C. X.

, X:

#define FUNCTION_LIST_A \
    X(myFunc1) \
    X(myFunc2) \
    X(otherFunc1) \
    X(otherFunc2) \
    X(defaultFunc)

:

#define X(name) FUNCTION_DEF(name)
FUNCTION_LIST_A
#undef X

:

FUNCTION_DEF(myFunc1)
FUNCTION_DEF(myFunc2)
FUNCTION_DEF(otherFunc1)
FUNCTION_DEF(otherFunc2)
FUNCTION_DEF(defaultFunc)

, , . , , ( ), , , , c.

+2

. - ( ) , :

#define M_NARGS(...) M_NARGS_(__VA_ARGS__, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
#define M_NARGS_(_10, _9, _8, _7, _6, _5, _4, _3, _2, _1, N, ...) N

#define M_CONC(A, B) M_CONC_(A, B)
#define M_CONC_(A, B) A##B
#define M_ID(...) __VA_ARGS__

#define M_FOR_EACH(ACTN, ...) M_CONC(M_FOR_EACH_, M_NARGS(__VA_ARGS__)) (ACTN, __VA_ARGS__)

#define M_FOR_EACH_0(ACTN, E) E
#define M_FOR_EACH_1(ACTN, E) ACTN(E)
#define M_FOR_EACH_2(ACTN, E, ...) ACTN(E) M_FOR_EACH_1(ACTN, __VA_ARGS__)
#define M_FOR_EACH_3(ACTN, E, ...) ACTN(E) M_FOR_EACH_2(ACTN, __VA_ARGS__)
#define M_FOR_EACH_4(ACTN, E, ...) ACTN(E) M_FOR_EACH_3(ACTN, __VA_ARGS__)
#define M_FOR_EACH_5(ACTN, E, ...) ACTN(E) M_FOR_EACH_4(ACTN, __VA_ARGS__)
//...etc

#define FUNCTION_DEF(func) extern int func(void);
#define FUNCTION_DEFS(...) M_FOR_EACH(FUNCTION_DEF, __VA_ARGS__)

, (, [1], [2]), , , , .

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+1

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