[Boost-commit] svn:boost r64227 - sandbox/SOC/2010/bit_masks/boost/integer/detail/bft

Subject: [Boost-commit] svn:boost r64227 - sandbox/SOC/2010/bit_masks/boost/integer/detail/bft
From: bbartmanboost_at_[hidden]
Date: 2010-07-21 14:55:21

Author: bbartman
Date: 2010-07-21 14:55:19 EDT (Wed, 21 Jul 2010)
New Revision: 64227
URL: http://svn.boost.org/trac/boost/changeset/64227

Log:
created better policy framework for reference type
Added:
   sandbox/SOC/2010/bit_masks/boost/integer/detail/bft/proxy_reference_policy.hpp   (contents, props changed)

Added: sandbox/SOC/2010/bit_masks/boost/integer/detail/bft/proxy_reference_policy.hpp
==============================================================================
--- (empty file)
+++ sandbox/SOC/2010/bit_masks/boost/integer/detail/bft/proxy_reference_policy.hpp	2010-07-21 14:55:19 EDT (Wed, 21 Jul 2010)
@@ -0,0 +1,87 @@
+//  Copyright 2010 Brian Bartman.
+//  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_BITFIELD_TUPLE_PROXY_REFERENCE_POLICY_HPP
+#define BOOST_BITFIELD_TUPLE_PROXY_REFERENCE_POLICY_HPP
+#include <boost/type_traits/is_same.hpp>
+#include <boost/type_traits/is_pod.hpp>
+#include <boost/mpl/void.hpp>
+#include <boost/mpl/logical.hpp>
+#include <boost/mpl/if.hpp>
+
+namespace boost { namespace detail {
+
+template <
+    typename StorageType,
+    typename Policy
+>
+struct policy_wrapper {
+    typedef StorageType                         storage_type;
+    typedef Policy                              field_policy;
+    typedef typename field_policy::value_type   value_type;
+
+    policy_wrapper(storage_type& storage)
+        :_field( storage )
+    { }
+
+    void set(value_type rhs) {
+        _field = field_policy::template apply<storage_type>::set(_field, rhs);
+    }
+
+    value_type get() const {
+        return field_policy::template apply<storage_type>::get( _field );
+    }
+
+private:
+    storage_type& _field;
+};
+
+/** This is the policy which is going to be used for calculating the correct
+ *  policy for retrieving the data from inside of teh bitfield_tuple
+ *  this is instead of the bitfield being the policy.
+ */
+template <
+    typename StorageType,
+    typename Offset,
+    typename Width,
+    typename ValueType,
+    typename Policy
+>
+struct select_packing_policy {
+    // this is where the correct storage and retrieval policy is
+    // selected based on the arguments supplied.
+    typedef typename mpl::if_<
+        is_same<
+            Policy,
+            mpl::void_
+        >,
+        typename mpl::if_<
+            is_pod<StorageType>,
+                ::boost::integer::bitfield<
+                    StorageType,
+                    Offset::value,
+                    Offset::value
+                      +
+                    Width::value - 1,
+                    ValueType
+                >,
+                ::boost::integer::bitfield<
+                    StorageType,
+                    Offset::value,
+                    Offset::value
+                      +
+                    Width::value - 1,
+                    ValueType
+                >
+        >::type,
+        policy_wrapper< StorageType, Policy >
+    >::type                         type;
+};
+
+
+}} // end boost::detial
+
+#endif