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#include <iostream>
#include <typeinfo>
 
template<int N, int D>
struct Modulus
{
        static auto const value = N % D;
};
 
template<int N>
struct Angle
{
        static auto const value = Modulus<N, 360>::value; // ERROR
        //static int const value = Modulus<N, 360>::value;  // OK
        //static auto const value = N % 360;                // OK
 
        typedef Angle<value> type;
};
 
int main()
{
        std::cout << typeid(Angle<30>::type).name() << "\n";
        std::cout << typeid(Angle<390>::type).name() << "\n";
 
        return 0;
}

prog.cpp: In instantiation of 'Angle<30>':
prog.cpp:22:38:   instantiated from here
prog.cpp:13:52: error: declaration of 'const auto Angle<30>::value' has no initializer
prog.cpp:13:52: error: invalid in-class initialization of static data member of non-integral type '<type error>'
prog.cpp: In instantiation of 'Angle<30>':
prog.cpp:22:38:   instantiated from here
prog.cpp:17:30: error: could not convert template argument 'Angle<30>::value' to 'int'
prog.cpp: In instantiation of 'Angle<390>':
prog.cpp:23:39:   instantiated from here
prog.cpp:13:52: error: declaration of 'const auto Angle<390>::value' has no initializer
prog.cpp:13:52: error: invalid in-class initialization of static data member of non-integral type '<type error>'
prog.cpp: In instantiation of 'Angle<390>':
prog.cpp:23:39:   instantiated from here
prog.cpp:17:30: error: could not convert template argument 'Angle<390>::value' to 'int'

Standard output is empty