annotate DEPENDENCIES/generic/include/boost/variant/recursive_wrapper_fwd.hpp @ 125:34e428693f5d vext

Vext -> Repoint
author Chris Cannam
date Thu, 14 Jun 2018 11:15:39 +0100
parents c530137014c0
children
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Chris@16 1 //-----------------------------------------------------------------------------
Chris@16 2 // boost variant/recursive_wrapper_fwd.hpp header file
Chris@16 3 // See http://www.boost.org for updates, documentation, and revision history.
Chris@16 4 //-----------------------------------------------------------------------------
Chris@16 5 //
Chris@16 6 // Copyright (c) 2002
Chris@16 7 // Eric Friedman, Itay Maman
Chris@16 8 //
Chris@16 9 // Portions Copyright (C) 2002 David Abrahams
Chris@16 10 //
Chris@16 11 // Distributed under the Boost Software License, Version 1.0. (See
Chris@16 12 // accompanying file LICENSE_1_0.txt or copy at
Chris@16 13 // http://www.boost.org/LICENSE_1_0.txt)
Chris@16 14
Chris@16 15 #ifndef BOOST_VARIANT_RECURSIVE_WRAPPER_FWD_HPP
Chris@16 16 #define BOOST_VARIANT_RECURSIVE_WRAPPER_FWD_HPP
Chris@16 17
Chris@16 18 #include "boost/mpl/aux_/config/ctps.hpp"
Chris@16 19
Chris@16 20 #include "boost/mpl/aux_/lambda_support.hpp"
Chris@16 21
Chris@16 22 // should be the last #include
Chris@16 23 #include "boost/type_traits/detail/bool_trait_def.hpp"
Chris@16 24
Chris@16 25 namespace boost {
Chris@16 26
Chris@16 27 //////////////////////////////////////////////////////////////////////////
Chris@16 28 // class template recursive_wrapper
Chris@16 29 //
Chris@16 30 // Enables recursive types in templates by breaking cyclic dependencies.
Chris@16 31 //
Chris@16 32 // For example:
Chris@16 33 //
Chris@16 34 // class my;
Chris@16 35 //
Chris@16 36 // typedef variant< int, recursive_wrapper<my> > var;
Chris@16 37 //
Chris@16 38 // class my {
Chris@16 39 // var var_;
Chris@16 40 // ...
Chris@16 41 // };
Chris@16 42 //
Chris@16 43 template <typename T> class recursive_wrapper;
Chris@16 44
Chris@16 45 ///////////////////////////////////////////////////////////////////////////////
Chris@16 46 // metafunction is_recursive_wrapper (modeled on code by David Abrahams)
Chris@16 47 //
Chris@16 48 // True iff specified type matches recursive_wrapper<T>.
Chris@16 49 //
Chris@16 50
Chris@16 51 namespace detail {
Chris@16 52
Chris@16 53
Chris@16 54 template <typename T>
Chris@16 55 struct is_recursive_wrapper_impl
Chris@16 56 : mpl::false_
Chris@16 57 {
Chris@16 58 };
Chris@16 59
Chris@16 60 template <typename T>
Chris@16 61 struct is_recursive_wrapper_impl< recursive_wrapper<T> >
Chris@16 62 : mpl::true_
Chris@16 63 {
Chris@16 64 };
Chris@16 65
Chris@16 66
Chris@16 67 } // namespace detail
Chris@16 68
Chris@16 69 BOOST_TT_AUX_BOOL_TRAIT_DEF1(
Chris@16 70 is_recursive_wrapper
Chris@16 71 , T
Chris@16 72 , (::boost::detail::is_recursive_wrapper_impl<T>::value)
Chris@16 73 )
Chris@16 74
Chris@16 75 ///////////////////////////////////////////////////////////////////////////////
Chris@16 76 // metafunction unwrap_recursive
Chris@16 77 //
Chris@16 78 // If specified type T matches recursive_wrapper<U>, then U; else T.
Chris@16 79 //
Chris@16 80
Chris@16 81
Chris@16 82 template <typename T>
Chris@16 83 struct unwrap_recursive
Chris@16 84 {
Chris@16 85 typedef T type;
Chris@16 86
Chris@16 87 BOOST_MPL_AUX_LAMBDA_SUPPORT(1,unwrap_recursive,(T))
Chris@16 88 };
Chris@16 89
Chris@16 90 template <typename T>
Chris@16 91 struct unwrap_recursive< recursive_wrapper<T> >
Chris@16 92 {
Chris@16 93 typedef T type;
Chris@16 94
Chris@16 95 BOOST_MPL_AUX_LAMBDA_SUPPORT_SPEC(1,unwrap_recursive,(T))
Chris@16 96 };
Chris@16 97
Chris@16 98
Chris@16 99 } // namespace boost
Chris@16 100
Chris@16 101 #include "boost/type_traits/detail/bool_trait_undef.hpp"
Chris@16 102
Chris@16 103 #endif // BOOST_VARIANT_RECURSIVE_WRAPPER_FWD_HPP