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Diffstat (limited to 'src/third_party/boost-1.56.0/boost/utility/declval.hpp')
| -rw-r--r-- | src/third_party/boost-1.56.0/boost/utility/declval.hpp | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/src/third_party/boost-1.56.0/boost/utility/declval.hpp b/src/third_party/boost-1.56.0/boost/utility/declval.hpp new file mode 100644 index 00000000000..a4ab2c8cb41 --- /dev/null +++ b/src/third_party/boost-1.56.0/boost/utility/declval.hpp @@ -0,0 +1,44 @@ +// declval.hpp -------------------------------------------------------------// + +// Copyright 2010 Vicente J. Botet Escriba + +// Distributed under the Boost Software License, Version 1.0. +// See http://www.boost.org/LICENSE_1_0.txt + +#ifndef BOOST_UTILITY_DECLVAL_HPP +#define BOOST_UTILITY_DECLVAL_HPP + +#include <boost/config.hpp> + +//----------------------------------------------------------------------------// + +#include <boost/type_traits/add_rvalue_reference.hpp> + +//----------------------------------------------------------------------------// +// // +// C++03 implementation of // +// 20.2.4 Function template declval [declval] // +// Written by Vicente J. Botet Escriba // +// // +// 1 The library provides the function template declval to simplify the +// definition of expressions which occur as unevaluated operands. +// 2 Remarks: If this function is used, the program is ill-formed. +// 3 Remarks: The template parameter T of declval may be an incomplete type. +// [ Example: +// +// template <class To, class From> +// decltype(static_cast<To>(declval<From>())) convert(From&&); +// +// declares a function template convert which only participates in overloading +// if the type From can be explicitly converted to type To. For another example +// see class template common_type (20.9.7.6). -end example ] +//----------------------------------------------------------------------------// + +namespace boost { + + template <typename T> + typename add_rvalue_reference<T>::type declval() BOOST_NOEXCEPT; // as unevaluated operand + +} // namespace boost + +#endif // BOOST_UTILITY_DECLVAL_HPP |