annotate DEPENDENCIES/generic/include/boost/detail/is_incrementable.hpp @ 16:2665513ce2d3

Add boost headers
author Chris Cannam
date Tue, 05 Aug 2014 11:11:38 +0100
parents
children c530137014c0
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Chris@16 1 // Copyright David Abrahams 2004. Use, modification and distribution is
Chris@16 2 // subject to the Boost Software License, Version 1.0. (See accompanying
Chris@16 3 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16 4 #ifndef IS_INCREMENTABLE_DWA200415_HPP
Chris@16 5 # define IS_INCREMENTABLE_DWA200415_HPP
Chris@16 6
Chris@16 7 # include <boost/type_traits/detail/template_arity_spec.hpp>
Chris@16 8 # include <boost/type_traits/remove_cv.hpp>
Chris@16 9 # include <boost/mpl/aux_/lambda_support.hpp>
Chris@16 10 # include <boost/mpl/bool.hpp>
Chris@16 11 # include <boost/detail/workaround.hpp>
Chris@16 12
Chris@16 13 // Must be the last include
Chris@16 14 # include <boost/type_traits/detail/bool_trait_def.hpp>
Chris@16 15
Chris@16 16 namespace boost { namespace detail {
Chris@16 17
Chris@16 18 // is_incrementable<T> metafunction
Chris@16 19 //
Chris@16 20 // Requires: Given x of type T&, if the expression ++x is well-formed
Chris@16 21 // it must have complete type; otherwise, it must neither be ambiguous
Chris@16 22 // nor violate access.
Chris@16 23
Chris@16 24 // This namespace ensures that ADL doesn't mess things up.
Chris@16 25 namespace is_incrementable_
Chris@16 26 {
Chris@16 27 // a type returned from operator++ when no increment is found in the
Chris@16 28 // type's own namespace
Chris@16 29 struct tag {};
Chris@16 30
Chris@16 31 // any soaks up implicit conversions and makes the following
Chris@16 32 // operator++ less-preferred than any other such operator that
Chris@16 33 // might be found via ADL.
Chris@16 34 struct any { template <class T> any(T const&); };
Chris@16 35
Chris@16 36 // This is a last-resort operator++ for when none other is found
Chris@16 37 # if BOOST_WORKAROUND(__GNUC__, == 4) && __GNUC_MINOR__ == 0 && __GNUC_PATCHLEVEL__ == 2
Chris@16 38
Chris@16 39 }
Chris@16 40
Chris@16 41 namespace is_incrementable_2
Chris@16 42 {
Chris@16 43 is_incrementable_::tag operator++(is_incrementable_::any const&);
Chris@16 44 is_incrementable_::tag operator++(is_incrementable_::any const&,int);
Chris@16 45 }
Chris@16 46 using namespace is_incrementable_2;
Chris@16 47
Chris@16 48 namespace is_incrementable_
Chris@16 49 {
Chris@16 50
Chris@16 51 # else
Chris@16 52
Chris@16 53 tag operator++(any const&);
Chris@16 54 tag operator++(any const&,int);
Chris@16 55
Chris@16 56 # endif
Chris@16 57
Chris@16 58 # if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3202)) \
Chris@16 59 || BOOST_WORKAROUND(BOOST_MSVC, <= 1300)
Chris@16 60 # define BOOST_comma(a,b) (a)
Chris@16 61 # else
Chris@16 62 // In case an operator++ is found that returns void, we'll use ++x,0
Chris@16 63 tag operator,(tag,int);
Chris@16 64 # define BOOST_comma(a,b) (a,b)
Chris@16 65 # endif
Chris@16 66
Chris@16 67 # if defined(BOOST_MSVC)
Chris@16 68 # pragma warning(push)
Chris@16 69 # pragma warning(disable:4913) // Warning about operator,
Chris@16 70 # endif
Chris@16 71
Chris@16 72 // two check overloads help us identify which operator++ was picked
Chris@16 73 char (& check_(tag) )[2];
Chris@16 74
Chris@16 75 template <class T>
Chris@16 76 char check_(T const&);
Chris@16 77
Chris@16 78
Chris@16 79 template <class T>
Chris@16 80 struct impl
Chris@16 81 {
Chris@16 82 static typename boost::remove_cv<T>::type& x;
Chris@16 83
Chris@16 84 BOOST_STATIC_CONSTANT(
Chris@16 85 bool
Chris@16 86 , value = sizeof(is_incrementable_::check_(BOOST_comma(++x,0))) == 1
Chris@16 87 );
Chris@16 88 };
Chris@16 89
Chris@16 90 template <class T>
Chris@16 91 struct postfix_impl
Chris@16 92 {
Chris@16 93 static typename boost::remove_cv<T>::type& x;
Chris@16 94
Chris@16 95 BOOST_STATIC_CONSTANT(
Chris@16 96 bool
Chris@16 97 , value = sizeof(is_incrementable_::check_(BOOST_comma(x++,0))) == 1
Chris@16 98 );
Chris@16 99 };
Chris@16 100
Chris@16 101 # if defined(BOOST_MSVC)
Chris@16 102 # pragma warning(pop)
Chris@16 103 # endif
Chris@16 104
Chris@16 105 }
Chris@16 106
Chris@16 107 # undef BOOST_comma
Chris@16 108
Chris@16 109 template<typename T>
Chris@16 110 struct is_incrementable
Chris@16 111 BOOST_TT_AUX_BOOL_C_BASE(::boost::detail::is_incrementable_::impl<T>::value)
Chris@16 112 {
Chris@16 113 BOOST_TT_AUX_BOOL_TRAIT_VALUE_DECL(::boost::detail::is_incrementable_::impl<T>::value)
Chris@16 114 BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_incrementable,(T))
Chris@16 115 };
Chris@16 116
Chris@16 117 template<typename T>
Chris@16 118 struct is_postfix_incrementable
Chris@16 119 BOOST_TT_AUX_BOOL_C_BASE(::boost::detail::is_incrementable_::impl<T>::value)
Chris@16 120 {
Chris@16 121 BOOST_TT_AUX_BOOL_TRAIT_VALUE_DECL(::boost::detail::is_incrementable_::postfix_impl<T>::value)
Chris@16 122 BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_postfix_incrementable,(T))
Chris@16 123 };
Chris@16 124
Chris@16 125 } // namespace detail
Chris@16 126
Chris@16 127 BOOST_TT_AUX_TEMPLATE_ARITY_SPEC(1, ::boost::detail::is_incrementable)
Chris@16 128 BOOST_TT_AUX_TEMPLATE_ARITY_SPEC(1, ::boost::detail::is_postfix_incrementable)
Chris@16 129
Chris@16 130 } // namespace boost
Chris@16 131
Chris@16 132 # include <boost/type_traits/detail/bool_trait_undef.hpp>
Chris@16 133
Chris@16 134 #endif // IS_INCREMENTABLE_DWA200415_HPP