how to use macro to generate function names like a factory

macro.c

#define CONCAT_2_EXPAND(A, B) A ## B
#define CONCAT_2(A, B) CONCAT_2_EXPAND(A, B)
#define CONCAT_3_EXPAND(A, B, C) A ## B ## C
#define CONCAT_3(A, B, C) CONCAT_3_EXPAND(A, B, C)

#define Vector_(NAME) CONCAT_3(Num, Vector_, NAME)
#define Vector CONCAT_2(Num, Vector)

#define num float
#define Num Float

struct Vector
{
 num *data;
 int n;
};

void Vector_(add)(Vector *C, Vector *A, Vector *B)
{
//codes
}

/*
real function after compilation :

void FloatVector_add(FloatVector *C, FloatVector *A, FloatVector *B)
{

}
*/