Updated boost to v1.55.0

[rsem.git] / boost / iterator / iterator_categories.hpp

diff --git a/boost/iterator/iterator_categories.hpp b/boost/iterator/iterator_categories.hpp
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+++ b/boost/iterator/iterator_categories.hpp
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+// (C) Copyright Jeremy Siek 2002.
+// Distributed under 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 BOOST_ITERATOR_CATEGORIES_HPP
+# define BOOST_ITERATOR_CATEGORIES_HPP
+
+# include <boost/config.hpp>
+# include <boost/detail/iterator.hpp>
+# include <boost/iterator/detail/config_def.hpp>
+
+# include <boost/detail/workaround.hpp>
+
+# include <boost/mpl/eval_if.hpp>
+# include <boost/mpl/identity.hpp>
+# include <boost/mpl/placeholders.hpp>
+# include <boost/mpl/aux_/lambda_support.hpp>
+
+# include <boost/type_traits/is_convertible.hpp>
+
+# include <boost/static_assert.hpp>
+
+namespace boost {
+
+//
+// Traversal Categories
+//
+
+struct no_traversal_tag {};
+
+struct incrementable_traversal_tag 
+  : no_traversal_tag
+{
+//     incrementable_traversal_tag() {}
+//     incrementable_traversal_tag(std::output_iterator_tag const&) {};
+};
+  
+struct single_pass_traversal_tag
+  : incrementable_traversal_tag
+{
+//     single_pass_traversal_tag() {}
+//     single_pass_traversal_tag(std::input_iterator_tag const&) {};
+};
+  
+struct forward_traversal_tag
+  : single_pass_traversal_tag
+{
+//     forward_traversal_tag() {}
+//     forward_traversal_tag(std::forward_iterator_tag const&) {};
+};
+  
+struct bidirectional_traversal_tag
+  : forward_traversal_tag
+{
+//     bidirectional_traversal_tag() {};
+//     bidirectional_traversal_tag(std::bidirectional_iterator_tag const&) {};
+};
+  
+struct random_access_traversal_tag
+  : bidirectional_traversal_tag
+{
+//     random_access_traversal_tag() {};
+//     random_access_traversal_tag(std::random_access_iterator_tag const&) {};
+};
+
+namespace detail
+{  
+  //
+  // Convert a "strictly old-style" iterator category to a traversal
+  // tag.  This is broken out into a separate metafunction to reduce
+  // the cost of instantiating iterator_category_to_traversal, below,
+  // for new-style types.
+  //
+  template <class Cat>
+  struct old_category_to_traversal
+    : mpl::eval_if<
+          is_convertible<Cat,std::random_access_iterator_tag>
+        , mpl::identity<random_access_traversal_tag>
+        , mpl::eval_if<
+              is_convertible<Cat,std::bidirectional_iterator_tag>
+            , mpl::identity<bidirectional_traversal_tag>
+            , mpl::eval_if<
+                  is_convertible<Cat,std::forward_iterator_tag>
+                , mpl::identity<forward_traversal_tag>
+                , mpl::eval_if<
+                      is_convertible<Cat,std::input_iterator_tag>
+                    , mpl::identity<single_pass_traversal_tag>
+                    , mpl::eval_if<
+                          is_convertible<Cat,std::output_iterator_tag>
+                        , mpl::identity<incrementable_traversal_tag>
+                        , void
+                      >
+                  >
+              >
+          >
+      >
+  {};
+
+# if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+  template <>
+  struct old_category_to_traversal<int>
+  {
+      typedef int type;
+  };
+# endif
+
+  template <class Traversal>
+  struct pure_traversal_tag
+    : mpl::eval_if<
+          is_convertible<Traversal,random_access_traversal_tag>
+        , mpl::identity<random_access_traversal_tag>
+        , mpl::eval_if<
+              is_convertible<Traversal,bidirectional_traversal_tag>
+            , mpl::identity<bidirectional_traversal_tag>
+            , mpl::eval_if<
+                  is_convertible<Traversal,forward_traversal_tag>
+                , mpl::identity<forward_traversal_tag>
+                , mpl::eval_if<
+                      is_convertible<Traversal,single_pass_traversal_tag>
+                    , mpl::identity<single_pass_traversal_tag>
+                    , mpl::eval_if<
+                          is_convertible<Traversal,incrementable_traversal_tag>
+                        , mpl::identity<incrementable_traversal_tag>
+                        , void
+                      >
+                  >
+              >
+          >
+      >
+  {
+  };
+  
+# if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+  template <>
+  struct pure_traversal_tag<int>
+  {
+      typedef int type;
+  };
+# endif
+
+} // namespace detail
+
+
+//
+// Convert an iterator category into a traversal tag
+//
+template <class Cat>
+struct iterator_category_to_traversal
+  : mpl::eval_if< // if already convertible to a traversal tag, we're done.
+        is_convertible<Cat,incrementable_traversal_tag>
+      , mpl::identity<Cat>
+      , boost::detail::old_category_to_traversal<Cat>
+    >
+{};
+
+// Trait to get an iterator's traversal category
+template <class Iterator = mpl::_1>
+struct iterator_traversal
+  : iterator_category_to_traversal<
+        typename boost::detail::iterator_traits<Iterator>::iterator_category
+    >
+{};
+
+# ifdef BOOST_MPL_CFG_NO_FULL_LAMBDA_SUPPORT
+// Hack because BOOST_MPL_AUX_LAMBDA_SUPPORT doesn't seem to work
+// out well.  Instantiating the nested apply template also
+// requires instantiating iterator_traits on the
+// placeholder. Instead we just specialize it as a metafunction
+// class.
+template <>
+struct iterator_traversal<mpl::_1>
+{
+    template <class T>
+    struct apply : iterator_traversal<T>
+    {};
+};
+template <>
+struct iterator_traversal<mpl::_>
+  : iterator_traversal<mpl::_1>
+{};
+# endif
+
+} // namespace boost
+
+#include <boost/iterator/detail/config_undef.hpp>
+
+#endif // BOOST_ITERATOR_CATEGORIES_HPP