| [/ |
| Copyright 2015 Peter Dimov. |
| Distributed under the Boost Software License, Version 1.0. |
| (See accompanying file LICENSE_1_0.txt or copy at |
| http://www.boost.org/LICENSE_1_0.txt). |
| ] |
| |
| [section:declval declval] |
| |
| template <class T> |
| typename add_rvalue_reference<T>::type declval() noexcept; // as unevaluated operand |
| |
| __std_ref 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>() )`. |
| |
| [endsect] |