|  | Home | Libraries | People | FAQ | More | 
template <class T> typename add_rvalue_reference<T>::type declval() noexcept; // as unevaluated operand
C++ Standard Reference: C++11 20.2.4 [declval].
        Header:  #include
        <boost/type_traits/declval.hpp>
        or  #include <boost/type_traits.hpp>
      
        The function template declval
        is used when a value of a certain type is required in a type computation
        context. For example, the type of the result of adding an int
        and a float can be obtained
        with the expression decltype( declval<int>()
        + declval<float>() ).