projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | //----------------------------------------------------------------------------- |
| 2 | // boost variant/detail/generic_result_type.hpp header file | |
| 3 | // See http://www.boost.org for updates, documentation, and revision history. | |
| 4 | //----------------------------------------------------------------------------- | |
| 5 | // | |
| 6 | // Copyright (c) 2003 | |
| 7 | // Eric Friedman | |
| 8 | // | |
| 9 | // Distributed under the Boost Software License, Version 1.0. (See | |
| 10 | // accompanying file LICENSE_1_0.txt or copy at | |
| 11 | // http://www.boost.org/LICENSE_1_0.txt) | |
| 12 | ||
| 13 | #ifndef BOOST_VARIANT_DETAIL_GENERIC_RESULT_TYPE_HPP | |
| 14 | #define BOOST_VARIANT_DETAIL_GENERIC_RESULT_TYPE_HPP | |
| 15 | ||
| 16 | #include <boost/config.hpp> | |
| 17 | ||
| 18 | ////////////////////////////////////////////////////////////////////////// | |
| 19 | // (workaround) macro BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE | |
| 20 | // | |
| 21 | // On compilers with BOOST_NO_VOID_RETURNS, this macro provides a route | |
| 22 | // to a single syntax for dealing with template functions that may (but | |
| 23 | // not necessarily) return nothing (i.e. void). | |
| 24 | // | |
| 25 | // BOOST_VARIANT_AUX_RETURN_VOID provided for compilers w/ (erroneous?) | |
| 26 | // warnings about non-void functions not returning a value. | |
| 27 | // | |
| 28 | ||
| 29 | #if !defined(BOOST_NO_VOID_RETURNS) | |
| 30 | ||
| 31 | #define BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(T) \ | |
| 32 | T \ | |
| 33 | /**/ | |
| 34 | ||
| 35 | #define BOOST_VARIANT_AUX_RETURN_VOID \ | |
| 36 | /**/ | |
| 37 | ||
| 38 | #define BOOST_VARIANT_AUX_RETURN_VOID_TYPE \ | |
| 39 | void \ | |
| 40 | /**/ | |
| 41 | ||
| 42 | #else // defined(BOOST_NO_VOID_RETURNS) | |
| 43 | ||
| 44 | namespace boost { | |
| 45 | namespace detail { namespace variant { | |
| 46 | ||
| 47 | struct fake_return_void | |
| 48 | { | |
| 49 | fake_return_void() | |
| 50 | { | |
| 51 | } | |
| 52 | ||
| 53 | template <typename T> | |
| 54 | fake_return_void(const T&) | |
| 55 | { | |
| 56 | } | |
| 57 | }; | |
| 58 | ||
| 59 | template <typename T> | |
| 60 | struct no_void_returns_helper | |
| 61 | { | |
| 62 | typedef T type; | |
| 63 | }; | |
| 64 | ||
| 65 | template <> | |
| 66 | struct no_void_returns_helper<void> | |
| 67 | { | |
| 68 | typedef fake_return_void type; | |
| 69 | }; | |
| 70 | ||
| 71 | }} // namespace detail::variant | |
| 72 | } // namespace boost | |
| 73 | ||
| 74 | #define BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(T) \ | |
| 75 | BOOST_DEDUCED_TYPENAME \ | |
| 76 | ::boost::detail::variant::no_void_returns_helper< T >::type \ | |
| 77 | /**/ | |
| 78 | ||
| 79 | #define BOOST_VARIANT_AUX_RETURN_VOID \ | |
| 80 | return ::boost::detail::variant::fake_return_void() \ | |
| 81 | /**/ | |
| 82 | ||
| 83 | #define BOOST_VARIANT_AUX_RETURN_VOID_TYPE \ | |
| 84 | ::boost::detail::variant::fake_return_void | |
| 85 | ||
| 86 | #endif // BOOST_NO_VOID_RETURNS workaround | |
| 87 | ||
| 88 | #endif // BOOST_VARIANT_DETAIL_GENERIC_RESULT_TYPE_HPP |