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Diffstat (limited to '3rdParty/Boost/boost/iterator/detail/facade_iterator_category.hpp')
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diff --git a/3rdParty/Boost/boost/iterator/detail/facade_iterator_category.hpp b/3rdParty/Boost/boost/iterator/detail/facade_iterator_category.hpp new file mode 100644 index 0000000..2c4771d --- /dev/null +++ b/3rdParty/Boost/boost/iterator/detail/facade_iterator_category.hpp @@ -0,0 +1,200 @@ +// Copyright David Abrahams 2003. 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 FACADE_ITERATOR_CATEGORY_DWA20031118_HPP +# define FACADE_ITERATOR_CATEGORY_DWA20031118_HPP + +# include <boost/iterator/iterator_categories.hpp> + +# include <boost/mpl/or.hpp> // used in iterator_tag inheritance logic +# include <boost/mpl/and.hpp> +# include <boost/mpl/if.hpp> +# include <boost/mpl/eval_if.hpp> +# include <boost/mpl/identity.hpp> +# include <boost/mpl/assert.hpp> + +# include <boost/type_traits/is_same.hpp> +# include <boost/type_traits/is_const.hpp> +# include <boost/type_traits/is_reference.hpp> +# include <boost/type_traits/is_convertible.hpp> + +# include <boost/type_traits/is_same.hpp> + +# include <boost/iterator/detail/config_def.hpp> // try to keep this last + +# ifdef BOOST_ITERATOR_REF_CONSTNESS_KILLS_WRITABILITY +# include <boost/detail/indirect_traits.hpp> +# endif + +// +// iterator_category deduction for iterator_facade +// + +// forward declaration +namespace boost { struct use_default; } + +namespace boost { namespace detail { + +struct input_output_iterator_tag + : std::input_iterator_tag +{ + // Using inheritance for only input_iterator_tag helps to avoid + // ambiguities when a stdlib implementation dispatches on a + // function which is overloaded on both input_iterator_tag and + // output_iterator_tag, as STLPort does, in its __valid_range + // function. I claim it's better to avoid the ambiguity in these + // cases. + operator std::output_iterator_tag() const + { + return std::output_iterator_tag(); + } +}; + +// +// True iff the user has explicitly disabled writability of this +// iterator. Pass the iterator_facade's Value parameter and its +// nested ::reference type. +// +template <class ValueParam, class Reference> +struct iterator_writability_disabled +# ifdef BOOST_ITERATOR_REF_CONSTNESS_KILLS_WRITABILITY // Adding Thomas' logic? + : mpl::or_< + is_const<Reference> + , boost::detail::indirect_traits::is_reference_to_const<Reference> + , is_const<ValueParam> + > +# else + : is_const<ValueParam> +# endif +{}; + + +// +// Convert an iterator_facade's traversal category, Value parameter, +// and ::reference type to an appropriate old-style category. +// +// If writability has been disabled per the above metafunction, the +// result will not be convertible to output_iterator_tag. +// +// Otherwise, if Traversal == single_pass_traversal_tag, the following +// conditions will result in a tag that is convertible both to +// input_iterator_tag and output_iterator_tag: +// +// 1. Reference is a reference to non-const +// 2. Reference is not a reference and is convertible to Value +// +template <class Traversal, class ValueParam, class Reference> +struct iterator_facade_default_category + : mpl::eval_if< + mpl::and_< + is_reference<Reference> + , is_convertible<Traversal,forward_traversal_tag> + > + , mpl::eval_if< + is_convertible<Traversal,random_access_traversal_tag> + , mpl::identity<std::random_access_iterator_tag> + , mpl::if_< + is_convertible<Traversal,bidirectional_traversal_tag> + , std::bidirectional_iterator_tag + , std::forward_iterator_tag + > + > + , typename mpl::eval_if< + mpl::and_< + is_convertible<Traversal, single_pass_traversal_tag> + + // check for readability + , is_convertible<Reference, ValueParam> + > + , mpl::identity<std::input_iterator_tag> + , mpl::identity<Traversal> + > + > +{ +}; + +// True iff T is convertible to an old-style iterator category. +template <class T> +struct is_iterator_category + : mpl::or_< + is_convertible<T,std::input_iterator_tag> + , is_convertible<T,std::output_iterator_tag> + > +{ +}; + +template <class T> +struct is_iterator_traversal + : is_convertible<T,incrementable_traversal_tag> +{}; + +// +// A composite iterator_category tag convertible to Category (a pure +// old-style category) and Traversal (a pure traversal tag). +// Traversal must be a strict increase of the traversal power given by +// Category. +// +template <class Category, class Traversal> +struct iterator_category_with_traversal + : Category, Traversal +{ +# if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) + // Make sure this isn't used to build any categories where + // convertibility to Traversal is redundant. Should just use the + // Category element in that case. + BOOST_MPL_ASSERT_NOT(( + is_convertible< + typename iterator_category_to_traversal<Category>::type + , Traversal + >)); + + BOOST_MPL_ASSERT((is_iterator_category<Category>)); + BOOST_MPL_ASSERT_NOT((is_iterator_category<Traversal>)); + BOOST_MPL_ASSERT_NOT((is_iterator_traversal<Category>)); +# if !BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1310)) + BOOST_MPL_ASSERT((is_iterator_traversal<Traversal>)); +# endif +# endif +}; + +// Computes an iterator_category tag whose traversal is Traversal and +// which is appropriate for an iterator +template <class Traversal, class ValueParam, class Reference> +struct facade_iterator_category_impl +{ +# if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) + BOOST_MPL_ASSERT_NOT((is_iterator_category<Traversal>)); +# endif + + typedef typename iterator_facade_default_category< + Traversal,ValueParam,Reference + >::type category; + + typedef typename mpl::if_< + is_same< + Traversal + , typename iterator_category_to_traversal<category>::type + > + , category + , iterator_category_with_traversal<category,Traversal> + >::type type; +}; + +// +// Compute an iterator_category for iterator_facade +// +template <class CategoryOrTraversal, class ValueParam, class Reference> +struct facade_iterator_category + : mpl::eval_if< + is_iterator_category<CategoryOrTraversal> + , mpl::identity<CategoryOrTraversal> // old-style categories are fine as-is + , facade_iterator_category_impl<CategoryOrTraversal,ValueParam,Reference> + > +{ +}; + +}} // namespace boost::detail + +# include <boost/iterator/detail/config_undef.hpp> + +#endif // FACADE_ITERATOR_CATEGORY_DWA20031118_HPP |