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Diffstat (limited to 'ext/boost/detail/is_incrementable.hpp')
-rw-r--r-- | ext/boost/detail/is_incrementable.hpp | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/ext/boost/detail/is_incrementable.hpp b/ext/boost/detail/is_incrementable.hpp new file mode 100644 index 0000000000..1c8fd5785b --- /dev/null +++ b/ext/boost/detail/is_incrementable.hpp @@ -0,0 +1,134 @@ +// Copyright David Abrahams 2004. Use, modification and distribution is +// subject to 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) +#ifndef IS_INCREMENTABLE_DWA200415_HPP +# define IS_INCREMENTABLE_DWA200415_HPP + +# include <boost/type_traits/detail/template_arity_spec.hpp> +# include <boost/type_traits/remove_cv.hpp> +# include <boost/mpl/aux_/lambda_support.hpp> +# include <boost/mpl/bool.hpp> +# include <boost/detail/workaround.hpp> + +// Must be the last include +# include <boost/type_traits/detail/bool_trait_def.hpp> + +namespace boost { namespace detail { + +// is_incrementable<T> metafunction +// +// Requires: Given x of type T&, if the expression ++x is well-formed +// it must have complete type; otherwise, it must neither be ambiguous +// nor violate access. + +// This namespace ensures that ADL doesn't mess things up. +namespace is_incrementable_ +{ + // a type returned from operator++ when no increment is found in the + // type's own namespace + struct tag {}; + + // any soaks up implicit conversions and makes the following + // operator++ less-preferred than any other such operator that + // might be found via ADL. + struct any { template <class T> any(T const&); }; + + // This is a last-resort operator++ for when none other is found +# if BOOST_WORKAROUND(__GNUC__, == 4) && __GNUC_MINOR__ == 0 && __GNUC_PATCHLEVEL__ == 2 + +} + +namespace is_incrementable_2 +{ + is_incrementable_::tag operator++(is_incrementable_::any const&); + is_incrementable_::tag operator++(is_incrementable_::any const&,int); +} +using namespace is_incrementable_2; + +namespace is_incrementable_ +{ + +# else + + tag operator++(any const&); + tag operator++(any const&,int); + +# endif + +# if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3202)) \ + || BOOST_WORKAROUND(BOOST_MSVC, <= 1300) +# define BOOST_comma(a,b) (a) +# else + // In case an operator++ is found that returns void, we'll use ++x,0 + tag operator,(tag,int); +# define BOOST_comma(a,b) (a,b) +# endif + +# if defined(BOOST_MSVC) +# pragma warning(push) +# pragma warning(disable:4913) // Warning about operator, +# endif + + // two check overloads help us identify which operator++ was picked + char (& check(tag) )[2]; + + template <class T> + char check(T const&); + + + template <class T> + struct impl + { + static typename boost::remove_cv<T>::type& x; + + BOOST_STATIC_CONSTANT( + bool + , value = sizeof(is_incrementable_::check(BOOST_comma(++x,0))) == 1 + ); + }; + + template <class T> + struct postfix_impl + { + static typename boost::remove_cv<T>::type& x; + + BOOST_STATIC_CONSTANT( + bool + , value = sizeof(is_incrementable_::check(BOOST_comma(x++,0))) == 1 + ); + }; + +# if defined(BOOST_MSVC) +# pragma warning(pop) +# endif + +} + +# undef BOOST_comma + +template<typename T> +struct is_incrementable +BOOST_TT_AUX_BOOL_C_BASE(::boost::detail::is_incrementable_::impl<T>::value) +{ + BOOST_TT_AUX_BOOL_TRAIT_VALUE_DECL(::boost::detail::is_incrementable_::impl<T>::value) + BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_incrementable,(T)) +}; + +template<typename T> +struct is_postfix_incrementable +BOOST_TT_AUX_BOOL_C_BASE(::boost::detail::is_incrementable_::impl<T>::value) +{ + BOOST_TT_AUX_BOOL_TRAIT_VALUE_DECL(::boost::detail::is_incrementable_::postfix_impl<T>::value) + BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_postfix_incrementable,(T)) +}; + +} // namespace detail + +BOOST_TT_AUX_TEMPLATE_ARITY_SPEC(1, ::boost::detail::is_incrementable) +BOOST_TT_AUX_TEMPLATE_ARITY_SPEC(1, ::boost::detail::is_postfix_incrementable) + +} // namespace boost + +# include <boost/type_traits/detail/bool_trait_undef.hpp> + +#endif // IS_INCREMENTABLE_DWA200415_HPP |