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#include <type_traits>
 
template <typename>
struct dependent_false { enum { value = false }; };
 
template <typename T>
struct foo : std::false_type { static_assert(dependent_false<T>::value, "Not lazy!"); };
template <>
struct foo<int> : std::true_type {};
 
template <typename T>
struct bar : foo<T> {};
 
template<typename... T>
struct And : std::true_type {};
 
template<typename T, typename... Ts>
struct And<T, Ts...>: std::integral_constant<bool, T::value && And<Ts...>::value> {};
 
int main() {
    return And<std::false_type, bar<double>>::value;
}
 

prog.cpp: In instantiation of 'foo<double>':
prog.cpp:12:21:   instantiated from 'bar<double>'
prog.cpp:18:83:   instantiated from 'And<bar<double> >'
prog.cpp:18:83:   instantiated from 'And<std::integral_constant<bool, false>, bar<double> >'
prog.cpp:21:45:   instantiated from here
prog.cpp:7:32: error: static assertion failed: "Not lazy!"

Standard output is empty