From eb5ef5e1343353fc0dde0aa2aa848793d2acadc5 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 24 Sep 2006 20:00:47 +0000
Subject: [PATCH] Move the hash extensions into their own header, which
 hopefully makes the extension implementation a little clearer. It also fixes
 a problem where the visual C++ include once pragma was preventing the
 extensions from being loaded on the second include.

[SVN r35314]
---
 include/boost/functional/hash.hpp            |   4 +
 include/boost/functional/hash/extensions.hpp | 182 +++++++++++++++++++
 include/boost/functional/hash/hash.hpp       | 174 ------------------
 3 files changed, 186 insertions(+), 174 deletions(-)
 create mode 100644 include/boost/functional/hash/extensions.hpp

diff --git a/include/boost/functional/hash.hpp b/include/boost/functional/hash.hpp
index 4bd1ee0..85d0156 100644
--- a/include/boost/functional/hash.hpp
+++ b/include/boost/functional/hash.hpp
@@ -8,3 +8,7 @@
 //  issue 6.18. 
 
 #include <boost/functional/hash/hash.hpp>
+
+#if !defined(BOOST_HASH_NO_EXTENSIONS)
+#include <boost/functional/hash/extensions.hpp>
+#endif
diff --git a/include/boost/functional/hash/extensions.hpp b/include/boost/functional/hash/extensions.hpp
new file mode 100644
index 0000000..c561bf4
--- /dev/null
+++ b/include/boost/functional/hash/extensions.hpp
@@ -0,0 +1,182 @@
+
+// Copyright 2005-2006 Daniel James.
+// 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)
+
+//  Based on Peter Dimov's proposal
+//  http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1756.pdf
+//  issue 6.18. 
+
+#if !defined(BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP)
+#define BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+namespace boost
+{
+
+#if defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
+    namespace hash_detail
+    {
+        template <bool IsArray>
+        struct call_hash_impl
+        {
+            template <class T>
+            struct inner
+            {
+                static std::size_t call(T const& v)
+                {
+                    using namespace boost;
+                    return hash_value(v);
+                }
+            };
+        };
+
+        template <>
+        struct call_hash_impl<true>
+        {
+            template <class Array>
+            struct inner
+            {
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+                static std::size_t call(Array const& v)
+#else
+                static std::size_t call(Array& v)
+#endif
+                {
+                    const int size = sizeof(v) / sizeof(*v);
+                    return boost::hash_range(v, v + size);
+                }
+            };
+        };
+
+        template <class T>
+        struct call_hash
+            : public call_hash_impl<boost::is_array<T>::value>
+                ::BOOST_NESTED_TEMPLATE inner<T>
+        {
+        };
+    }
+#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
+
+#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
+
+    template <class T> struct hash
+        : std::unary_function<T, std::size_t>
+    {
+#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
+        std::size_t operator()(T const& val) const
+        {
+            return hash_value(val);
+        }
+#else
+        std::size_t operator()(T const& val) const
+        {
+            return hash_detail::call_hash<T>::call(val);
+        }
+#endif
+    };
+
+#if BOOST_WORKAROUND(__DMC__, <= 0x848)
+    template <class T, unsigned int n> struct hash<T[n]>
+        : std::unary_function<T[n], std::size_t>
+    {
+        std::size_t operator()(const T* val) const
+        {
+            return boost::hash_range(val, val+n);
+        }
+    };
+#endif
+
+#else // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
+
+    // On compilers without partial specialization, boost::hash<T>
+    // has already been declared to deal with pointers, so just
+    // need to supply the non-pointer version.
+
+    namespace hash_detail
+    {
+        template <bool IsPointer>
+        struct hash_impl;
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+
+        template <>
+        struct hash_impl<false>
+        {
+            template <class T>
+            struct inner
+                : std::unary_function<T, std::size_t>
+            {
+#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
+                std::size_t operator()(T const& val) const
+                {
+                    return hash_value(val);
+                }
+#else
+                std::size_t operator()(T const& val) const
+                {
+                    return hash_detail::call_hash<T>::call(val);
+                }
+#endif
+            };
+        };
+
+#else // Visual C++ 6.5
+
+    // There's probably a more elegant way to Visual C++ 6.5 to work
+    // but I don't know what it is.
+
+        template <bool IsConst>
+        struct hash_impl_msvc
+        {
+            template <class T>
+            struct inner
+                : public std::unary_function<T, std::size_t>
+            {
+                std::size_t operator()(T const& val) const
+                {
+                    return hash_detail::call_hash<T const>::call(val);
+                }
+
+                std::size_t operator()(T& val) const
+                {
+                    return hash_detail::call_hash<T>::call(val);
+                }
+            };
+        };
+
+        template <>
+        struct hash_impl_msvc<true>
+        {
+            template <class T>
+            struct inner
+                : public std::unary_function<T, std::size_t>
+            {
+                std::size_t operator()(T& val) const
+                {
+                    return hash_detail::call_hash<T>::call(val);
+                }
+            };
+        };
+        
+        template <class T>
+        struct hash_impl_msvc2
+            : public hash_impl_msvc<boost::is_const<T>::value>
+                    ::BOOST_NESTED_TEMPLATE inner<T> {};
+        
+        template <>
+        struct hash_impl<false>
+        {
+            template <class T>
+            struct inner : public hash_impl_msvc2<T> {};
+        };
+
+#endif // Visual C++ 6.5
+    }
+#endif  // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
+}
+
+#endif
diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index e42a801..20a381a 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -473,177 +473,3 @@ namespace boost
 }
 
 #endif // BOOST_FUNCTIONAL_HASH_HASH_HPP
-
-////////////////////////////////////////////////////////////////////////////////
-
-#if !defined(BOOST_HASH_NO_EXTENSIONS) \
-    && !defined(BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP)
-#define BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP
-
-namespace boost
-{
-
-#if defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
-    namespace hash_detail
-    {
-        template <bool IsArray>
-        struct call_hash_impl
-        {
-            template <class T>
-            struct inner
-            {
-                static std::size_t call(T const& v)
-                {
-                    using namespace boost;
-                    return hash_value(v);
-                }
-            };
-        };
-
-        template <>
-        struct call_hash_impl<true>
-        {
-            template <class Array>
-            struct inner
-            {
-#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
-                static std::size_t call(Array const& v)
-#else
-                static std::size_t call(Array& v)
-#endif
-                {
-                    const int size = sizeof(v) / sizeof(*v);
-                    return boost::hash_range(v, v + size);
-                }
-            };
-        };
-
-        template <class T>
-        struct call_hash
-            : public call_hash_impl<boost::is_array<T>::value>
-                ::BOOST_NESTED_TEMPLATE inner<T>
-        {
-        };
-    }
-#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
-
-#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
-
-    template <class T> struct hash
-        : std::unary_function<T, std::size_t>
-    {
-#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
-        std::size_t operator()(T const& val) const
-        {
-            return hash_value(val);
-        }
-#else
-        std::size_t operator()(T const& val) const
-        {
-            return hash_detail::call_hash<T>::call(val);
-        }
-#endif
-    };
-
-#if BOOST_WORKAROUND(__DMC__, <= 0x848)
-    template <class T, unsigned int n> struct hash<T[n]>
-        : std::unary_function<T[n], std::size_t>
-    {
-        std::size_t operator()(const T* val) const
-        {
-            return boost::hash_range(val, val+n);
-        }
-    };
-#endif
-
-#else // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
-
-    // On compilers without partial specialization, boost::hash<T>
-    // has already been declared to deal with pointers, so just
-    // need to supply the non-pointer version.
-
-    namespace hash_detail
-    {
-        template <bool IsPointer>
-        struct hash_impl;
-
-#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
-
-        template <>
-        struct hash_impl<false>
-        {
-            template <class T>
-            struct inner
-                : std::unary_function<T, std::size_t>
-            {
-#if !defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING)
-                std::size_t operator()(T const& val) const
-                {
-                    return hash_value(val);
-                }
-#else
-                std::size_t operator()(T const& val) const
-                {
-                    return hash_detail::call_hash<T>::call(val);
-                }
-#endif
-            };
-        };
-
-#else // Visual C++ 6.5
-
-    // There's probably a more elegant way to Visual C++ 6.5 to work
-    // but I don't know what it is.
-
-        template <bool IsConst>
-        struct hash_impl_msvc
-        {
-            template <class T>
-            struct inner
-                : public std::unary_function<T, std::size_t>
-            {
-                std::size_t operator()(T const& val) const
-                {
-                    return hash_detail::call_hash<T const>::call(val);
-                }
-
-                std::size_t operator()(T& val) const
-                {
-                    return hash_detail::call_hash<T>::call(val);
-                }
-            };
-        };
-
-        template <>
-        struct hash_impl_msvc<true>
-        {
-            template <class T>
-            struct inner
-                : public std::unary_function<T, std::size_t>
-            {
-                std::size_t operator()(T& val) const
-                {
-                    return hash_detail::call_hash<T>::call(val);
-                }
-            };
-        };
-        
-        template <class T>
-        struct hash_impl_msvc2
-            : public hash_impl_msvc<boost::is_const<T>::value>
-                    ::BOOST_NESTED_TEMPLATE inner<T> {};
-        
-        template <>
-        struct hash_impl<false>
-        {
-            template <class T>
-            struct inner : public hash_impl_msvc2<T> {};
-        };
-
-#endif // Visual C++ 6.5
-    }
-#endif  // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
-}
-
-#endif
-