c++ - 拥有超过 64 个成员的 BOOST_FUSION_ADAPT_STRUCT 是怎么回事？

Question

尝试为拥有超过 64 个成员和 BOOST_FUSION_ADAPT_STRUCT 宏的巨大结构创建样板代码，但它无法在 VS2015 Update 3 中编译。我尝试使用 BOOST_FUSION_HAS_VARIADIC_VECTOR 和 BOOST_PP_LIMIT_TUPLE 但运气不好，如果我向 BOOST_FUSION_ADAPT_STRUCT 添加超过 64 个成员，我会不断收到相同的错误。没有发现任何关于 BOOST_FUSION_ADAPT_STRUCT 的限制的提及，除非它处于 C++03 模式。我错过了什么吗？

住在Coliru

代码:

#include <boost/fusion/adapted/struct/adapt_struct.hpp>

struct Data
{
    int a01 = 1;
    int a02 = 1;
    int a03 = 1;
    int a04 = 1;
    int a05 = 1;
    int a06 = 1;
    int a07 = 1;
    int a08 = 1;
    int a09 = 1;
    int a10 = 1;
    int a11 = 1;
    int a12 = 1;
    int a13 = 1;
    int a14 = 1;
    int a15 = 1;
    int a16 = 1;
    int a17 = 1;
    int a18 = 1;
    int a19 = 1;
    int a20 = 1;
    int a21 = 1;
    int a22 = 1;
    int a23 = 1;
    int a24 = 1;
    int a25 = 1;
    int a26 = 1;
    int a27 = 1;
    int a28 = 1;
    int a29 = 1;
    int a30 = 1;
    int a31 = 1;
    int a32 = 1;
    int a33 = 1;
    int a34 = 1;
    int a35 = 1;
    int a36 = 1;
    int a37 = 1;
    int a38 = 1;
    int a39 = 1;
    int a40 = 1;
    int a41 = 1;
    int a42 = 1;
    int a43 = 1;
    int a44 = 1;
    int a45 = 1;
    int a46 = 1;
    int a47 = 1;
    int a48 = 1;
    int a49 = 1;
    int a50 = 1;
    int a51 = 1;
    int a52 = 1;
    int a53 = 1;
    int a54 = 1;
    int a55 = 1;
    int a56 = 1;
    int a57 = 1;
    int a58 = 1;
    int a59 = 1;
    int a60 = 1;
    int a61 = 1;
    int a62 = 1;
    int a63 = 1;
    int a64 = 1;
    int a65 = 1;
    int a66 = 1;
    int a67 = 1;
    int a68 = 1;
    int a69 = 1;
    int a70 = 1;
};

BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17,
                          a18, a19, a20, a21, a22, a23, a24, a25, a26, a27, a28, a29, a30, a31, a32, a33, a34, a35, a36,
                          a37, a38, a39, a40, a41, a42, a43, a44, a45, a46, a47, a48, a49, a50, a51, a52, a53, a54, a55,
                          a56, a57, a58, a59, a60, a61, a62, a63/*, a64, a65, a66, a67, a68, a69, a70*/) // uncomment the a64 to get the error


int main()
{
    return 0;
}

MSVC 错误:

1>consoleapplication23.cpp(119): warning C4003: not enough actual parameters for macro 'BOOST_PP_SEQ_ELEM_III' 1>consoleapplication23.cpp(119): error C2065: 'BOOST_PP_SEQ_ELEM_0': undeclared identifier 1>consoleapplication23.cpp(119): error C2146: syntax error: missing '>' before identifier 'BOOST_PP_TUPLE_TO_SEQ_a64' 1>consoleapplication23.cpp(119): error C2065: 'a01': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a02': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a03': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a04': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a05': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a06': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a07': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a08': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a09': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a10': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a11': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a12': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a13': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a14': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a15': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a16': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a17': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a18': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a19': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a20': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a21': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a22': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a23': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a24': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a25': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a26': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a27': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a28': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a29': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a30': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a31': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a32': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a33': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a34': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a35': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a36': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a37': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a38': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a39': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a40': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a41': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a42': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a43': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a44': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a45': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a46': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a47': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a48': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a49': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a50': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a51': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a52': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a53': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a54': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a55': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a56': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a57': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a58': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a59': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a60': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a61': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a62': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a63': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a64': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a65': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a66': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a67': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a68': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a69': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a70': undeclared identifier 1>consoleapplication23.cpp(116): error C2059: syntax error: ')' 1>consoleapplication23.cpp(119): error C2977: 'boost::fusion::traits::tag_of': too many template arguments 1> packages\boost.1.61.0.0\lib\native\include\boost\fusion\support\tag_of.hpp(71): note: see declaration of 'boost::fusion::traits::tag_of' 1>consoleapplication23.cpp(119): error C2913: explicit specialization; 'boost::fusion::traits::tag_of' is not a specialization of a class template 1>consoleapplication23.cpp(119): error C2913: explicit specialization; 'boost::fusion::traits::tag_of' is not a specialization of a class template 1>consoleapplication23.cpp(119): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int 1>consoleapplication23.cpp(119): error C2440: 'initializing': cannot convert from 'initializer list' to 'int' 1> consoleapplication23.cpp(119): note: The initializer contains too many elements 1>consoleapplication23.cpp(116): error C2059: syntax error: '(' 1>consoleapplication23.cpp(119): error C2065: 'BOOST_PP_SEQ_ELEM_0': undeclared identifier 1>consoleapplication23.cpp(119): error C2146: syntax error: missing '>' before identifier 'BOOST_PP_TUPLE_TO_SEQ_a64' 1>consoleapplication23.cpp(119): error C2065: 'a01': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a02': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a03': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a04': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a05': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a06': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a07': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a08': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a09': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a10': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a11': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a12': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a13': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a14': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a15': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a16': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a17': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a18': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a19': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a20': undeclared identifier 1>consoleapplication23.cpp(119): error C2065: 'a21': undeclared identifier 1>consoleapplication23.cpp(119): fatal error C1003: error count exceeds 100; stopping compilation

海湾合作委员会错误:

main.cpp:80:1: error: macro "BOOST_PP_SEQ_ELEM_III" requires 2 arguments, but only 1 given a56, a57, a58, a59, a60, a61, a62, a63, a64, a65, a66, a67, a68, a69, a70) // uncomment the a64 to get the error ^ In file included from /usr/local/include/boost/preprocessor/seq/seq.hpp:16:0, from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:20, from main.cpp:1: main.cpp:77:1: error: 'BOOST_PP_SEQ_ELEM_III' was not declared in this scope BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:28:0, from main.cpp:1: main.cpp:77:1: error: template argument 1 is invalid BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/preprocessor/seq/seq.hpp:16:0, from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:20, from main.cpp:1: main.cpp:77:1: error: 'BOOST_PP_SEQ_ELEM_III' was not declared in this scope BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:28:0, from main.cpp:1: main.cpp:77:1: error: template argument 1 is invalid BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/preprocessor/control/if.hpp:18:0, from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:17, from main.cpp:1: main.cpp:77:1: error: 'BOOST_PP_IIF_0' does not name a type BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/preprocessor/seq/seq.hpp:16:0, from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:20, from main.cpp:1: main.cpp:77:1: error: 'BOOST_PP_SEQ_ELEM_III' was not declared in this scope BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:28:0, from main.cpp:1: main.cpp:77:1: error: template argument 1 is invalid BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/preprocessor/seq/seq.hpp:16:0, from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:20, from main.cpp:1: main.cpp:77:1: error: 'BOOST_PP_SEQ_ELEM_III' was not declared in this scope BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:28:0, from main.cpp:1: main.cpp:77:1: error: template argument 1 is invalid BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/preprocessor/seq/seq.hpp:16:0, from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:20, from main.cpp:1: main.cpp:77:1: error: 'BOOST_PP_SEQ_ELEM_III' was not declared in this scope BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^ In file included from /usr/local/include/boost/fusion/adapted/struct/adapt_struct.hpp:28:0, from main.cpp:1: main.cpp:77:1: error: template argument 1 is invalid BOOST_FUSION_ADAPT_STRUCT(Data, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15, a16, a17, ^

g++ -std=c++14 -O2 -Wall -pedantic -pthread main.cpp && ./a.out

Answer 1

看起来 BOOST_FUSION_ADAPT_STRUCT 每个类元素都有两个参数，类型和名称。 MSVC 只支持 127 macro parameters而标准建议使用 255。这解释了为什么第 64 个元素(需要 128 个宏参数)无法在 MSVC++ 上编译。