初始化使用宏用C未知大小的二维数组 [英] Initialize a 2D array of unknown size using macros in C

问题描述

我工作，需要我去一个2维数组文本传递到像这样我的宏的一个小宏项目： myMacro（{{0，1，2}，{2,1 ，0}}）。无需通过数组文本宏的大小，有没有办法把它扩展到以下内容： INT [2] [3] = {{0，1，2}，{ 2，1，0}} 或等价的东西（即$ p $任何初始化pserves阵列的形状将工作）？感谢您事先的任何帮助。

解决方案

 的#include＆LT;升压/ preprocessor ​​/元组/ size.hpp＆GT;
＃包括LT＆;升压/ preprocessor ​​/元组/ elem.hpp＆GT;
＃包括LT＆;升压/ preprocessor ​​/可变参数/ to_seq.hpp＆GT;
＃包括LT＆;升压/ preprocessor ​​/ SEQ / for_each.hpp＆GT;＃定义VA（...）__VA_ARGS__
＃定义TRANS（R，数据，ELEM）{VA ELEM}，＃定义myMacro（姓名，ARG）\\
    INT名[BOOST_PP_TUPLE_SIZE（ARG）] [BOOST_PP_TUPLE_SIZE（BOOST_PP_TUPLE_ELEM（0，ARG））= \\
    {BOOST_PP_SEQ_FOR_EACH（TRANS，BOOST_PP_VARIADIC_TO_SEQ ARG）}诠释主（）{
    myMacro（一，（（1,2,3），（4,5,6）））; // = GT;诠释一个[2] [3] = {{1,2,3}，{4,5 ，6}，};
    返回0;
}
 

I was working on a small macro project that requires me to pass a 2 dimensional array literal to one of my macros like so: myMacro({{0, 1, 2}, {2, 1, 0}}). Without having to pass the size of the array literal to the macro, is there a way to have it expand to the following: int[2][3] = { {0, 1, 2}, {2, 1, 0} } or something equivalent (any initialization that preserves the shape of the array will work)? Thanks in advance for any help

解决方案

#include <boost/preprocessor/tuple/size.hpp>
#include <boost/preprocessor/tuple/elem.hpp>
#include <boost/preprocessor/variadic/to_seq.hpp>
#include <boost/preprocessor/seq/for_each.hpp>

#define VA(...) __VA_ARGS__
#define TRANS(r, data, elem) { VA elem},

#define myMacro(name, arg)\
    int name[BOOST_PP_TUPLE_SIZE(arg)][BOOST_PP_TUPLE_SIZE(BOOST_PP_TUPLE_ELEM(0,arg))] = \
    { BOOST_PP_SEQ_FOR_EACH(TRANS, , BOOST_PP_VARIADIC_TO_SEQ arg)}

int main(){
    myMacro(a, ((1,2,3),(4,5,6)) );//=>int a[2][3] = { { 1,2,3}, { 4,5,6}, };
    return 0;
}

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