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#include <iostream>
#include <string>
#include <vector>
#include <set>
 
namespace FileSystem {
    struct Info {
        std::string path;
    };
}
 
#define STATIC_ASSERT(cond, msg) \
typedef char static_assert_##msg[2*(!!cond)-1];
 
#define CREATE_MEMBER_DETECTOR(member) \
template<typename T> \
class detector_of_##member { \
private: \
    typedef char Yes[1]; \
    typedef char No[2]; \
    struct Base {char member;}; \
    struct Derived: T, Base {}; \
    \
    template<typename PointerToMember, PointerToMember> \
    struct Check {}; \
    \
    template<typename D> \
    static Yes& result(...); \
    template<typename D> \
    static No& result(Check<char Base::*, &D::member>*); \
    \
public: \
    enum {value = sizeof(result<Derived>(0)) == 1}; \
};
 
CREATE_MEMBER_DETECTOR(push_back)
CREATE_MEMBER_DETECTOR(path)
 
typedef std::set<FileSystem::Info> X;
typedef std::vector<std::string> Y;
typedef std::vector<FileSystem::Info> Z;
int main()
{
    STATIC_ASSERT(detector_of_push_back<X>::value, no_push_back);
    STATIC_ASSERT(detector_of_push_back<Y>::value, no_push_back);
    STATIC_ASSERT(detector_of_path<Y::value_type>::value, no_path);
    STATIC_ASSERT(detector_of_path<Z::value_type>::value, no_path);
}

prog.cpp: In function ‘int main()’:
prog.cpp:13:46: error: size of array ‘static_assert_no_push_back’ is negative
 typedef char static_assert_##msg[2*(!!cond)-1];
                                              ^
prog.cpp:44:5: note: in expansion of macro ‘STATIC_ASSERT’
     STATIC_ASSERT(detector_of_push_back<X>::value, no_push_back);
     ^
prog.cpp:13:46: error: size of array ‘static_assert_no_path’ is negative
 typedef char static_assert_##msg[2*(!!cond)-1];
                                              ^
prog.cpp:46:5: note: in expansion of macro ‘STATIC_ASSERT’
     STATIC_ASSERT(detector_of_path<Y::value_type>::value, no_path);
     ^

Standard output is empty