From 2553a5fbdc2d842f54b9becd607dcd6c6dff96ba Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Tue, 6 Jul 2010 23:32:37 +0000
Subject: [PATCH 01/22] Try preventing static casts when calling `hash_value`.

[SVN r63716]
---
 include/boost/functional/hash/hash.hpp |  9 +++++++++
 test/Jamfile.v2                        |  2 ++
 test/implicit_fail_test.cpp            | 16 ++++++++++++++++
 test/shared_ptr_fail_test.cpp          | 11 +++++++++++
 4 files changed, 38 insertions(+)
 create mode 100644 test/implicit_fail_test.cpp
 create mode 100644 test/shared_ptr_fail_test.cpp

diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index e85ca5a..bd8d37f 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -15,6 +15,7 @@
 #include <boost/functional/hash/detail/hash_float.hpp>
 #include <string>
 #include <boost/limits.hpp>
+#include <boost/static_assert.hpp>
 
 #if defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
 #include <boost/type_traits/is_pointer.hpp>
@@ -29,6 +30,14 @@
 
 namespace boost
 {
+    // If you get a static assertion here, it's because hash_value
+    // isn't declared for your type.
+    template <typename T>
+    std::size_t hash_value(T const&) {
+        BOOST_STATIC_ASSERT((T*) 0 && false);
+        return 0;
+    }
+
     std::size_t hash_value(bool);
     std::size_t hash_value(char);
     std::size_t hash_value(unsigned char);
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 4435dd2..c2d8084 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -50,6 +50,8 @@ test-suite functional/hash
         [ run container_no_fwd_test.cpp ]
         [ compile-fail hash_no_ext_fail_test.cpp ]
         [ compile-fail namespace_fail_test.cpp ]
+        [ compile-fail implicit_fail_test.cpp ]
+        [ compile-fail shared_ptr_fail_test.cpp ]
         [ run hash_no_ext_macro_1.cpp ]
         [ run hash_no_ext_macro_2.cpp ]
     ;
diff --git a/test/implicit_fail_test.cpp b/test/implicit_fail_test.cpp
new file mode 100644
index 0000000..1dd0555
--- /dev/null
+++ b/test/implicit_fail_test.cpp
@@ -0,0 +1,16 @@
+#include <boost/functional/hash.hpp>
+
+namespace test
+{
+    struct base {};
+    std::size_t hash_value(base const&) { return 0; }
+    
+    struct converts { operator base() const { return base(); } };
+}
+
+int main() {
+    boost::hash<test::converts> hash;
+    test::converts x;
+    
+    hash(x);
+}
\ No newline at end of file
diff --git a/test/shared_ptr_fail_test.cpp b/test/shared_ptr_fail_test.cpp
new file mode 100644
index 0000000..584739f
--- /dev/null
+++ b/test/shared_ptr_fail_test.cpp
@@ -0,0 +1,11 @@
+#include <boost/functional/hash.hpp>
+#include <boost/shared_ptr.hpp>
+
+// This should obviously pass if shared_ptr ever supports Boost.Hash.
+
+int main() {
+    boost::hash<boost::shared_ptr<int> > hash;
+    boost::shared_ptr<int> x(new int(10));
+    
+    hash(x);
+}
\ No newline at end of file

From 38d131c158c4c680b4a89b6eee7ef375bfb0bf90 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Thu, 8 Jul 2010 20:48:30 +0000
Subject: [PATCH 02/22] Fix inspect issues.

[SVN r63762]
---
 test/implicit_fail_test.cpp   | 7 ++++++-
 test/shared_ptr_fail_test.cpp | 7 ++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/test/implicit_fail_test.cpp b/test/implicit_fail_test.cpp
index 1dd0555..e48bbcd 100644
--- a/test/implicit_fail_test.cpp
+++ b/test/implicit_fail_test.cpp
@@ -1,3 +1,8 @@
+
+// Copyright 2010 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)
+
 #include <boost/functional/hash.hpp>
 
 namespace test
@@ -13,4 +18,4 @@ int main() {
     test::converts x;
     
     hash(x);
-}
\ No newline at end of file
+}
diff --git a/test/shared_ptr_fail_test.cpp b/test/shared_ptr_fail_test.cpp
index 584739f..b0e045f 100644
--- a/test/shared_ptr_fail_test.cpp
+++ b/test/shared_ptr_fail_test.cpp
@@ -1,3 +1,8 @@
+
+// Copyright 2010 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)
+
 #include <boost/functional/hash.hpp>
 #include <boost/shared_ptr.hpp>
 
@@ -8,4 +13,4 @@ int main() {
     boost::shared_ptr<int> x(new int(10));
     
     hash(x);
-}
\ No newline at end of file
+}

From bbfb6fd32c405b18527f615be6c7d6c455ce5780 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 10 Jul 2010 13:47:47 +0000
Subject: [PATCH 03/22] Release notes for hash.

[SVN r63810]
---
 doc/changes.qbk                        | 8 ++++++++
 include/boost/functional/hash/hash.hpp | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/doc/changes.qbk b/doc/changes.qbk
index 4e0d0a9..bc6f4ca 100644
--- a/doc/changes.qbk
+++ b/doc/changes.qbk
@@ -106,4 +106,12 @@
   Avoid hashing 0.5 and 0 to the same number.
 * Stop using deprecated `BOOST_HAS_*` macros.
 
+[h2 Boost 1.44.0]
+
+* Prevent implicit conversions when calling `hash_value`. If you find
+  that the new version breaks your code, you can enable the old
+  behaviour by defining `BOOST_HASH_ALLOW_IMPLICIT_CASTS` - although
+  I would recommend that you update your code to work with the new
+  version.
+
 [endsect]
diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index bd8d37f..54407d6 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -30,6 +30,8 @@
 
 namespace boost
 {
+#if !defined(BOOST_HASH_ALLOW_IMPLICIT_CASTS)
+
     // If you get a static assertion here, it's because hash_value
     // isn't declared for your type.
     template <typename T>
@@ -38,6 +40,8 @@ namespace boost
         return 0;
     }
 
+#endif
+
     std::size_t hash_value(bool);
     std::size_t hash_value(char);
     std::size_t hash_value(unsigned char);

From 906f6327069ec8aff234f26e3540ee133877a81c Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Wed, 14 Jul 2010 08:17:48 +0000
Subject: [PATCH 04/22] Actually, make the change to hash opt-in, rather than
 opt-out. It's a bit late to introduce a breaking change.

[SVN r64007]
---
 doc/changes.qbk                        | 15 ++++++++++-----
 include/boost/functional/hash/hash.hpp |  2 +-
 test/Jamfile.v2                        |  1 +
 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/doc/changes.qbk b/doc/changes.qbk
index bc6f4ca..eec4876 100644
--- a/doc/changes.qbk
+++ b/doc/changes.qbk
@@ -108,10 +108,15 @@
 
 [h2 Boost 1.44.0]
 
-* Prevent implicit conversions when calling `hash_value`. If you find
-  that the new version breaks your code, you can enable the old
-  behaviour by defining `BOOST_HASH_ALLOW_IMPLICIT_CASTS` - although
-  I would recommend that you update your code to work with the new
-  version.
+* Add option to prevent implicit conversions when calling `hash_value` by
+  defining `BOOST_HASH_NO_IMPLICIT_CASTS`. When using `boost::hash`
+  for a type that does not have `hash_value` declared but does have
+  an implicit conversion to a type that does, it would use that
+  implicit conversion to hash it. Which can sometimes go very wrong,
+  e.g. using a conversion to bool and only hashing to 2 possible
+  values. Since fixing this is a breaking change and was only
+  approached quite late in the release cycle with little discussion
+  it's opt-in for now. This, or something like it, will become the
+  default in a future version.
 
 [endsect]
diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 54407d6..24a78f3 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -30,7 +30,7 @@
 
 namespace boost
 {
-#if !defined(BOOST_HASH_ALLOW_IMPLICIT_CASTS)
+#if defined(BOOST_HASH_NO_IMPLICIT_CASTS)
 
     // If you get a static assertion here, it's because hash_value
     // isn't declared for your type.
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index c2d8084..1b35eed 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -7,6 +7,7 @@ import testing ;
 
 project hash-tests
     : requirements
+        <define>BOOST_HASH_NO_IMPLICIT_CASTS
         <warnings>all
         <toolset>intel:<warnings>on
         <toolset>intel:<cxxflags>-strict-ansi

From fc3b3863b4da1128a537ce7dbf5a659257c604b7 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Wed, 14 Jul 2010 08:28:04 +0000
Subject: [PATCH 05/22] Only include static_assert when necessary.

[SVN r64009]
---
 include/boost/functional/hash/hash.hpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 24a78f3..108d3ed 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -15,7 +15,10 @@
 #include <boost/functional/hash/detail/hash_float.hpp>
 #include <string>
 #include <boost/limits.hpp>
+
+#if defined(BOOST_HASH_NO_IMPLICIT_CASTS)
 #include <boost/static_assert.hpp>
+#endif
 
 #if defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
 #include <boost/type_traits/is_pointer.hpp>

From 577054de93c45090dc6faf3ff6d87efde3a25e7b Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Tue, 27 Jul 2010 19:18:53 +0000
Subject: [PATCH 06/22] Fix hashing pointers on 64-bit OpenVMS.

Patch by Artyom. Refs #4477

[SVN r64397]
---
 include/boost/functional/hash/hash.hpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 108d3ed..0eedf7f 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -209,9 +209,15 @@ namespace boost
     template <class T> std::size_t hash_value(T* v)
 #endif
     {
+#if defined(__VMS) && __INITIAL_POINTER_SIZE == 64
+	// for some reason ptrdiff_t on OpenVMS compiler with
+	// 64 bit is not 64 bit !!!
+        std::size_t x = static_cast<std::size_t>(
+           reinterpret_cast<long long int>(v));
+#else
         std::size_t x = static_cast<std::size_t>(
            reinterpret_cast<std::ptrdiff_t>(v));
-
+#endif
         return x + (x >> 3);
     }
 

From 982b350d71698ac31a1b5a7ef642bad002387f85 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 14 Nov 2010 11:42:58 +0000
Subject: [PATCH 07/22] Remove some 'always_show_run_output' flags.

[SVN r66566]
---
 test/Jamfile.v2 | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 1b35eed..de35142 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -25,8 +25,8 @@ test-suite functional/hash
         [ run hash_number_test.cpp ]
         [ run hash_pointer_test.cpp ]
         [ run hash_function_pointer_test.cpp ]
-        [ run hash_float_test.cpp : : : <test-info>always_show_run_output ]
-        [ run hash_long_double_test.cpp : : : <test-info>always_show_run_output ]
+        [ run hash_float_test.cpp ]
+        [ run hash_long_double_test.cpp ]
         [ run hash_string_test.cpp ]
         [ run hash_range_test.cpp ]
         [ run hash_custom_test.cpp ]

From a2e947588dddaa6a741d7685632f5a72a49db859 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Tue, 7 Dec 2010 20:45:08 +0000
Subject: [PATCH 08/22] Import boostbook/quickbook in unordered and hash docs.

[SVN r67091]
---
 doc/Jamfile.v2 | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/doc/Jamfile.v2 b/doc/Jamfile.v2
index 1aab1e9..044ee70 100644
--- a/doc/Jamfile.v2
+++ b/doc/Jamfile.v2
@@ -3,6 +3,9 @@
 # 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)
 
+using boostbook ;
+using quickbook ;
+
 xml hash : hash.qbk ;
 boostbook standalone : hash :
     <xsl:param>boost.root=../../../..

From 482f038837bf213ca0823a069e6d1057e9925ed8 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 11 Dec 2010 14:43:00 +0000
Subject: [PATCH 09/22] Avoid `-Wconversion` warnings in unordered & hash.

[SVN r67170]
---
 doc/changes.qbk                                             | 4 ++++
 include/boost/functional/hash/detail/hash_float_generic.hpp | 4 ++--
 test/Jamfile.v2                                             | 4 ++--
 test/hash_complex_test.cpp                                  | 2 +-
 test/hash_number_test.cpp                                   | 3 ++-
 5 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/doc/changes.qbk b/doc/changes.qbk
index eec4876..eb6572f 100644
--- a/doc/changes.qbk
+++ b/doc/changes.qbk
@@ -119,4 +119,8 @@
   it's opt-in for now. This, or something like it, will become the
   default in a future version.
 
+[h2 Boost 1.46.0]
+
+* Avoid warning due with gcc's `-Wconversion` flag.
+
 [endsect]
diff --git a/include/boost/functional/hash/detail/hash_float_generic.hpp b/include/boost/functional/hash/detail/hash_float_generic.hpp
index fdbf53f..1278c2f 100644
--- a/include/boost/functional/hash/detail/hash_float_generic.hpp
+++ b/include/boost/functional/hash/detail/hash_float_generic.hpp
@@ -53,7 +53,7 @@ namespace boost
 
             v = ldexp(v, limits<std::size_t>::digits);
             std::size_t seed = static_cast<std::size_t>(v);
-            v -= seed;
+            v -= static_cast<T>(seed);
 
             // ceiling(digits(T) * log2(radix(T))/ digits(size_t)) - 1;
             std::size_t const length
@@ -66,7 +66,7 @@ namespace boost
             {
                 v = ldexp(v, limits<std::size_t>::digits);
                 std::size_t part = static_cast<std::size_t>(v);
-                v -= part;
+                v -= static_cast<T>(part);
                 hash_float_combine(seed, part);
             }
 
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index de35142..8985875 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -11,8 +11,8 @@ project hash-tests
         <warnings>all
         <toolset>intel:<warnings>on
         <toolset>intel:<cxxflags>-strict-ansi
-        <toolset>gcc:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter"
-        <toolset>darwin:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter"
+        <toolset>gcc:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter -Wconversion"
+        <toolset>darwin:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter -Wconversion"
         <toolset>msvc:<warnings-as-errors>on
         #<toolset>gcc:<warnings-as-errors>on
         #<toolset>darwin:<warnings-as-errors>on
diff --git a/test/hash_complex_test.cpp b/test/hash_complex_test.cpp
index a2a2dc2..67e2aff 100644
--- a/test/hash_complex_test.cpp
+++ b/test/hash_complex_test.cpp
@@ -69,7 +69,7 @@ void complex_float_tests(Float*)
     generic_complex_tests(complex(0.5,0));
     generic_complex_tests(complex(25,0));
     generic_complex_tests(complex(25,0));
-    generic_complex_tests(complex(-67.5324535,56.23578678));
+    generic_complex_tests(complex(static_cast<Float>(-67.5324535),static_cast<Float>(56.23578678)));
 }
 
 template <class Integer>
diff --git a/test/hash_number_test.cpp b/test/hash_number_test.cpp
index 91b9b92..1080860 100644
--- a/test/hash_number_test.cpp
+++ b/test/hash_number_test.cpp
@@ -113,7 +113,8 @@ void poor_quality_tests(T*)
     if(T(1) != T(2))
         BOOST_TEST(x1(T(1)) !=  x2(T(2)));
     if((limits::max)() != (limits::max)() - 1)
-        BOOST_TEST(x1((limits::max)()) != x2((limits::max)() - 1));
+        BOOST_TEST(x1(static_cast<T>((limits::max)()))
+        	!= x2(static_cast<T>((limits::max)() - 1)));
 }
 
 void bool_test()

From ed598f865e181cd4fc6b3da7fb4d2d911a628c15 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Mon, 3 Jan 2011 12:43:34 +0000
Subject: [PATCH 10/22] Fix tabs and files without copyright.

[SVN r67612]
---
 include/boost/functional/hash/hash.hpp | 4 ++--
 test/hash_number_test.cpp              | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 0eedf7f..389804c 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -210,8 +210,8 @@ namespace boost
 #endif
     {
 #if defined(__VMS) && __INITIAL_POINTER_SIZE == 64
-	// for some reason ptrdiff_t on OpenVMS compiler with
-	// 64 bit is not 64 bit !!!
+    // for some reason ptrdiff_t on OpenVMS compiler with
+    // 64 bit is not 64 bit !!!
         std::size_t x = static_cast<std::size_t>(
            reinterpret_cast<long long int>(v));
 #else
diff --git a/test/hash_number_test.cpp b/test/hash_number_test.cpp
index 1080860..b989d22 100644
--- a/test/hash_number_test.cpp
+++ b/test/hash_number_test.cpp
@@ -114,7 +114,7 @@ void poor_quality_tests(T*)
         BOOST_TEST(x1(T(1)) !=  x2(T(2)));
     if((limits::max)() != (limits::max)() - 1)
         BOOST_TEST(x1(static_cast<T>((limits::max)()))
-        	!= x2(static_cast<T>((limits::max)() - 1)));
+            != x2(static_cast<T>((limits::max)() - 1)));
 }
 
 void bool_test()

From ad614b3d5f1c3e7eb31a08e0624e04f65af3e650 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Tue, 4 Jan 2011 23:30:22 +0000
Subject: [PATCH 11/22] Move tests for container_fwd.hpp into detail.

[SVN r67667]
---
 test/Jamfile.v2                |   6 --
 test/container_fwd_test.cpp    | 114 ---------------------------------
 test/container_no_fwd_test.cpp |  14 ----
 3 files changed, 134 deletions(-)
 delete mode 100644 test/container_fwd_test.cpp
 delete mode 100644 test/container_no_fwd_test.cpp

diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 8985875..f7fe7d9 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -43,12 +43,6 @@ test-suite functional/hash
         [ run link_test.cpp link_test_2.cpp ]
         [ run link_ext_test.cpp link_no_ext_test.cpp ]
         [ run extensions_hpp_test.cpp ]
-        [ run container_fwd_test.cpp ]
-        [ run container_fwd_test.cpp : :
-            :   <toolset>gcc:<define>_GLIBCXX_DEBUG
-                <toolset>darwin:<define>_GLIBCXX_DEBUG
-            :   container_fwd_gcc_debug ]
-        [ run container_no_fwd_test.cpp ]
         [ compile-fail hash_no_ext_fail_test.cpp ]
         [ compile-fail namespace_fail_test.cpp ]
         [ compile-fail implicit_fail_test.cpp ]
diff --git a/test/container_fwd_test.cpp b/test/container_fwd_test.cpp
deleted file mode 100644
index ec8cc54..0000000
--- a/test/container_fwd_test.cpp
+++ /dev/null
@@ -1,114 +0,0 @@
-
-// Copyright 2005-2009 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)
-
-#include "./config.hpp"
-
-#include <boost/functional/detail/container_fwd.hpp>
-
-#if BOOST_WORKAROUND(__GNUC__, < 3) && \
-    !defined(__SGI_STL_PORT) && !defined(_STLPORT_VERSION)
-template <class charT, class Allocator>
-static void test(
-    std::basic_string<charT, std::string_char_traits<charT>, Allocator> const&)
-{
-}
-#else
-template <class charT, class Allocator>
-static void test(
-    std::basic_string<charT, std::char_traits<charT>, Allocator> const&)
-{
-}
-#endif
-    
-template <class T, class Allocator>
-static void test(std::deque<T, Allocator> const&)
-{
-}
-
-template <class T, class Allocator>
-static void test(std::list<T, Allocator> const&)
-{
-}
-
-template <class T, class Allocator>
-static void test(std::vector<T, Allocator> const&)
-{
-}
-
-template <class Key, class T, class Compare, class Allocator>
-static void test(std::map<Key, T, Compare, Allocator> const&)
-{
-}
-
-template <class Key, class T, class Compare, class Allocator>
-static void test(std::multimap<Key, T, Compare, Allocator> const&)
-{
-}
-
-template <class Key, class Compare, class Allocator>
-static void test(std::set<Key, Compare, Allocator> const&)
-{
-}
-
-template <class Key, class Compare, class Allocator>
-static void test(std::multiset<Key, Compare, Allocator> const&)
-{
-}
-
-template <std::size_t N>
-static void test(std::bitset<N> const&)
-{
-}
-
-template <class T>
-static void test(std::complex<T> const&)
-{
-}
-
-template <class X, class Y>
-static void test(std::pair<X, Y> const&)
-{
-}
-
-#include <deque>
-#include <list>
-#include <vector>
-#include <map>
-#include <set>
-#include <bitset>
-#include <string>
-#include <complex>
-#include <utility>
-
-int main()
-{
-    std::deque<int> x1;
-    std::list<std::string> x2;
-    std::vector<float> x3;
-    std::vector<bool> x4;
-    std::map<int, int> x5;
-    std::multimap<float, int*> x6;
-    std::set<std::string> x7;
-    std::multiset<std::vector<int> > x8;
-    std::bitset<10> x9;
-    std::string x10;
-    std::complex<double> x11;
-    std::pair<std::list<int>, char***> x12;
-
-    test(x1);
-    test(x2);
-    test(x3);
-    test(x4);
-    test(x5);
-    test(x6);
-    test(x7);
-    test(x8);
-    test(x9);
-    test(x10);
-    test(x11);
-    test(x12);
-
-    return 0;
-}
diff --git a/test/container_no_fwd_test.cpp b/test/container_no_fwd_test.cpp
deleted file mode 100644
index 9da09da..0000000
--- a/test/container_no_fwd_test.cpp
+++ /dev/null
@@ -1,14 +0,0 @@
-
-// Copyright 2010 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)
-
-#define BOOST_DETAIL_NO_CONTAINER_FWD
-
-#include <boost/detail/container_fwd.hpp>
-
-int main()
-{
-    std::set<int> x;
-    std::vector<std::string> y;
-}

From 7dc95d044d2cba7ce5cdd5f902281ba11c049bd5 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Fri, 14 Jan 2011 03:13:39 +0000
Subject: [PATCH 12/22] Support typeindex in hash. Refs #4756.

[SVN r68145]
---
 doc/ref.xml                            | 34 ++++++++++++++++++
 include/boost/functional/hash/hash.hpp | 20 +++++++++++
 test/Jamfile.v2                        |  1 +
 test/hash_type_index_test.cpp          | 48 ++++++++++++++++++++++++++
 4 files changed, 103 insertions(+)
 create mode 100644 test/hash_type_index_test.cpp

diff --git a/doc/ref.xml b/doc/ref.xml
index 47a09d5..318bf85 100644
--- a/doc/ref.xml
+++ b/doc/ref.xml
@@ -406,6 +406,29 @@ file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
         </method>
       </struct-specialization>
 
+      <struct-specialization name="hash">
+        <template></template>
+        <specialization>
+          <template-arg>std::type_index</template-arg>
+        </specialization>
+        <method name="operator()" cv="const">
+          <type>std::size_t</type>
+          <parameter name="val">
+            <paramtype>std::type_index</paramtype>
+          </parameter>
+          <returns>
+            <para><code>val.hash_code()</code></para>
+          </returns>
+          <throws><para>Doesn't throw</para></throws>
+        </method>
+        <notes>
+          <para>
+            Only available if it's in your standard library and Boost.Config
+            is aware of it.
+          </para>
+        </notes>
+      </struct-specialization>
+
       <free-function-group name="Support functions (Boost extension)."> 
 
       <!--
@@ -716,6 +739,11 @@ for(; first != last; ++first)
           <parameter name="val"><paramtype>std::complex&lt;T&gt; const&amp;</paramtype></parameter>
         </signature>
 
+        <signature>
+          <type>std::size_t</type>
+          <parameter name="val"><paramtype>std::type_index</paramtype></parameter>
+        </signature>
+
         <description><para>
           Generally shouldn't be called directly by users, instead they should use
           <classname>boost::hash</classname>, <functionname>boost::hash_range</functionname>
@@ -798,6 +826,12 @@ return seed;</programlisting></entry>
                   </entry>
                   <entry>When <code>T</code> is a built in type and <code>val.imag() == 0</code>, the result is equal to <code>hash_value(val.real())</code>. Otherwise an unspecified value, except that equal arguments shall yield the same result.</entry>
                 </row>
+                <row>
+                  <entry>
+                    <code>std::type_index</code>
+                  </entry>
+                  <entry><code>val.hash_code()</code></entry>
+                </row>
               </tbody>
             </tgroup>
           </informaltable>
diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 389804c..2d99c6c 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -24,6 +24,10 @@
 #include <boost/type_traits/is_pointer.hpp>
 #endif
 
+#if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
+#include <typeindex>
+#endif
+
 #if BOOST_WORKAROUND(__GNUC__, < 3) \
     && !defined(__SGI_STL_PORT) && !defined(_STLPORT_VERSION)
 #define BOOST_HASH_CHAR_TRAITS string_char_traits
@@ -87,6 +91,11 @@ namespace boost
     std::size_t hash_value(
         std::basic_string<Ch, std::BOOST_HASH_CHAR_TRAITS<Ch>, A> const&);
 
+#if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
+    template <class Ch, class A>
+    std::size_t hash_value(std::type_index);
+#endif
+
     // Implementation
 
     namespace hash_detail
@@ -331,6 +340,13 @@ namespace boost
         return boost::hash_detail::float_hash_value(v);
     }
 
+#if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
+    std::size_t hash_value(std::type_index v)
+    {
+        return v.hash_code();
+    }
+#endif
+
     //
     // boost::hash
     //
@@ -435,6 +451,10 @@ namespace boost
     BOOST_HASH_SPECIALIZE(boost::ulong_long_type)
 #endif
 
+#if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
+    BOOST_HASH_SPECIALIZE(std::type_index)
+#endif
+
 #undef BOOST_HASH_SPECIALIZE
 #undef BOOST_HASH_SPECIALIZE_REF
 
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index f7fe7d9..34294f0 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -40,6 +40,7 @@ test-suite functional/hash
         [ run hash_set_test.cpp ]
         [ run hash_map_test.cpp ]
         [ run hash_complex_test.cpp ]
+        [ run hash_type_index_test.cpp ]
         [ run link_test.cpp link_test_2.cpp ]
         [ run link_ext_test.cpp link_no_ext_test.cpp ]
         [ run extensions_hpp_test.cpp ]
diff --git a/test/hash_type_index_test.cpp b/test/hash_type_index_test.cpp
new file mode 100644
index 0000000..7892918
--- /dev/null
+++ b/test/hash_type_index_test.cpp
@@ -0,0 +1,48 @@
+
+// Copyright 2011 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)
+
+#include "./config.hpp"
+
+#ifdef TEST_STD_INCLUDES
+#  include <functional>
+#else
+#  include <boost/functional/hash.hpp>
+#endif
+#include <boost/config.hpp>
+#include <boost/detail/lightweight_test.hpp>
+
+#if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
+
+#include <typeindex>
+
+void test_type_index() {
+    std::type_index int_index = typeid(int);
+    std::type_index int2_index = typeid(int);
+    std::type_index char_index = typeid(char);
+    
+    HASH_NAMESPACE::hash<std::type_index> hasher;
+    
+    BOOST_TEST(hasher(int_index) == int_index.hash_code());
+    BOOST_TEST(hasher(int_index) == int2_index.hash_code());
+    BOOST_TEST(hasher(char_index) == char_index.hash_code());
+    BOOST_TEST(HASH_NAMESPACE::hash_value(int_index) == int_index.hash_code());
+    BOOST_TEST(HASH_NAMESPACE::hash_value(int_index) == int2_index.hash_code());
+    BOOST_TEST(HASH_NAMESPACE::hash_value(char_index) == char_index.hash_code());
+
+    BOOST_TEST(hasher(int_index) == hasher(int2_index));
+    BOOST_TEST(hasher(int_index) != hasher(char_index));
+}
+#endif
+
+int main()
+{
+#if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
+    test_type_index();
+#else
+    std::cout<<"<type_index> not available."<<std::endl;
+#endif
+
+    return boost::report_errors();
+}

From 9e641187c6f505afc4737923971225576c7d1fa9 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Fri, 14 Jan 2011 03:36:39 +0000
Subject: [PATCH 13/22] Oops, make new hash_value overload inline.

[SVN r68147]
---
 include/boost/functional/hash/hash.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 2d99c6c..97aaf9c 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -341,7 +341,7 @@ namespace boost
     }
 
 #if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
-    std::size_t hash_value(std::type_index v)
+    inline std::size_t hash_value(std::type_index v)
     {
         return v.hash_code();
     }

From ce885af9b03ef328813d93274bd13d9ef596ba8c Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 16 Jan 2011 11:06:00 +0000
Subject: [PATCH 14/22] Fix copy and paste typo. Refs #4756.

[SVN r68182]
---
 include/boost/functional/hash/hash.hpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 97aaf9c..51ec860 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -92,7 +92,6 @@ namespace boost
         std::basic_string<Ch, std::BOOST_HASH_CHAR_TRAITS<Ch>, A> const&);
 
 #if !defined(BOOST_NO_0X_HDR_TYPEINDEX)
-    template <class Ch, class A>
     std::size_t hash_value(std::type_index);
 #endif
 

From 664522596ff32f03a6d1fab63cdd4f87a7dcc7c9 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Fri, 11 Mar 2011 18:17:48 +0000
Subject: [PATCH 15/22] Remove shared_ptr fail test since it now supports
 Boost.Hash

[SVN r69853]
---
 test/Jamfile.v2               |  1 -
 test/shared_ptr_fail_test.cpp | 16 ----------------
 2 files changed, 17 deletions(-)
 delete mode 100644 test/shared_ptr_fail_test.cpp

diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 34294f0..2c65685 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -47,7 +47,6 @@ test-suite functional/hash
         [ compile-fail hash_no_ext_fail_test.cpp ]
         [ compile-fail namespace_fail_test.cpp ]
         [ compile-fail implicit_fail_test.cpp ]
-        [ compile-fail shared_ptr_fail_test.cpp ]
         [ run hash_no_ext_macro_1.cpp ]
         [ run hash_no_ext_macro_2.cpp ]
     ;
diff --git a/test/shared_ptr_fail_test.cpp b/test/shared_ptr_fail_test.cpp
deleted file mode 100644
index b0e045f..0000000
--- a/test/shared_ptr_fail_test.cpp
+++ /dev/null
@@ -1,16 +0,0 @@
-
-// Copyright 2010 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)
-
-#include <boost/functional/hash.hpp>
-#include <boost/shared_ptr.hpp>
-
-// This should obviously pass if shared_ptr ever supports Boost.Hash.
-
-int main() {
-    boost::hash<boost::shared_ptr<int> > hash;
-    boost::shared_ptr<int> x(new int(10));
-    
-    hash(x);
-}

From 8c0e9a2b09832395c602d9837ef94d3e3302c269 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Fri, 11 Mar 2011 18:19:23 +0000
Subject: [PATCH 16/22] Run some tests without BOOST_HASH_NO_IMPLICIT_CASTS.

[SVN r69854]
---
 test/Jamfile.v2 | 75 +++++++++++++++++++++++++++++--------------------
 1 file changed, 44 insertions(+), 31 deletions(-)

diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 2c65685..7b3ccd9 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -1,5 +1,5 @@
 
-# Copyright 2005-2008 Daniel James.
+# Copyright 2005-2011 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)
 
@@ -7,7 +7,6 @@ import testing ;
 
 project hash-tests
     : requirements
-        <define>BOOST_HASH_NO_IMPLICIT_CASTS
         <warnings>all
         <toolset>intel:<warnings>on
         <toolset>intel:<cxxflags>-strict-ansi
@@ -20,35 +19,49 @@ project hash-tests
 
 test-suite functional/hash
     :
-        [ run hash_fwd_test_1.cpp ]
-        [ run hash_fwd_test_2.cpp ]
-        [ run hash_number_test.cpp ]
-        [ run hash_pointer_test.cpp ]
-        [ run hash_function_pointer_test.cpp ]
-        [ run hash_float_test.cpp ]
-        [ run hash_long_double_test.cpp ]
-        [ run hash_string_test.cpp ]
-        [ run hash_range_test.cpp ]
-        [ run hash_custom_test.cpp ]
-        [ run hash_global_namespace_test.cpp ]
-        [ run hash_friend_test.cpp ]
-        [ run hash_built_in_array_test.cpp ]
-        [ run hash_value_array_test.cpp ]
-        [ run hash_vector_test.cpp ]
-        [ run hash_list_test.cpp ]
-        [ run hash_deque_test.cpp ]
-        [ run hash_set_test.cpp ]
-        [ run hash_map_test.cpp ]
-        [ run hash_complex_test.cpp ]
-        [ run hash_type_index_test.cpp ]
-        [ run link_test.cpp link_test_2.cpp ]
-        [ run link_ext_test.cpp link_no_ext_test.cpp ]
-        [ run extensions_hpp_test.cpp ]
-        [ compile-fail hash_no_ext_fail_test.cpp ]
-        [ compile-fail namespace_fail_test.cpp ]
-        [ compile-fail implicit_fail_test.cpp ]
-        [ run hash_no_ext_macro_1.cpp ]
-        [ run hash_no_ext_macro_2.cpp ]
+        [ run hash_fwd_test_1.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_fwd_test_2.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_number_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_pointer_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_function_pointer_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_float_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_long_double_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_string_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_range_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_custom_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_global_namespace_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_friend_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_built_in_array_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_value_array_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_vector_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_list_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_deque_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_set_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_map_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_complex_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_type_index_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run link_test.cpp link_test_2.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run link_ext_test.cpp link_no_ext_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run extensions_hpp_test.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ compile-fail hash_no_ext_fail_test.cpp : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ compile-fail namespace_fail_test.cpp : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ compile-fail implicit_fail_test.cpp : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_no_ext_macro_1.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+        [ run hash_no_ext_macro_2.cpp : : : <define>BOOST_HASH_NO_IMPLICIT_CASTS ]
+    ;
+
+test-suite functional/hash_implicit_casts
+    :
+        [ run hash_number_test.cpp : : : : implicit_number ]
+        [ run hash_pointer_test.cpp : : : : implicit_pointer ]
+        [ run hash_function_pointer_test.cpp : : : : implicit_function_pointer ]
+        [ run hash_float_test.cpp : : : : implicit_float ]
+        [ run hash_string_test.cpp : : : : implicit_string ]
+        [ run hash_range_test.cpp : : : : implicit_range ]
+        [ run hash_custom_test.cpp : : : : implicit_custom ]
+        [ run hash_built_in_array_test.cpp : : : : implicit_built_in_array ]
+        [ run link_test.cpp link_test_2.cpp : : : : implicit_link ]
+        [ run implicit_fail_test.cpp : : : : implicit_test ]
     ;
 
 test-suite functional/hash_no_ext

From da096ddf8cb1ca2deaa2b9f9557e63024f6f4a41 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 9 Oct 2011 18:14:50 +0000
Subject: [PATCH 17/22] Hash: Note about the quality of the hash function.

In response to the thread starting at:

http://lists.boost.org/Archives/boost/2011/10/186476.php

[SVN r74856]
---
 doc/hash.qbk      |  5 +++++
 doc/intro.qbk     | 10 ++++++---
 doc/rationale.qbk | 55 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 67 insertions(+), 3 deletions(-)
 create mode 100644 doc/rationale.qbk

diff --git a/doc/hash.qbk b/doc/hash.qbk
index b734fb4..fe428f3 100644
--- a/doc/hash.qbk
+++ b/doc/hash.qbk
@@ -14,11 +14,16 @@
     ]
 ]
 
+[def __issues__
+    [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1837.pdf
+    Library Extension Technical Report Issues List]]
+
 [include:hash intro.qbk]
 [include:hash tutorial.qbk]
 [include:hash portability.qbk]
 [include:hash disable.qbk]
 [include:hash changes.qbk]
+[include:hash rationale.qbk]
 [xinclude ref.xml]
 [include:hash links.qbk]
 [include:hash thanks.qbk]
diff --git a/doc/intro.qbk b/doc/intro.qbk
index b027719..076e997 100644
--- a/doc/intro.qbk
+++ b/doc/intro.qbk
@@ -18,9 +18,6 @@
 [def __multi-index-short__ [@boost:/libs/multi_index/doc/index.html
     Boost.MultiIndex]]
 [def __bimap__ [@boost:/libs/bimap/index.html Boost.Bimap]]
-[def __issues__
-    [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1837.pdf
-    Library Extension Technical Report Issues List]]
 [def __hash-function__ [@http://en.wikipedia.org/wiki/Hash_function hash function]]
 [def __hash-table__ [@http://en.wikipedia.org/wiki/Hash_table hash table]]
 
@@ -44,5 +41,12 @@ __issues__ (page 63), this adds support for:
 * the standard containers.
 * extending [classref boost::hash] for custom types.
 
+[note
+This hash function is designed to be used in containers based on
+the STL and is not suitable as a general purpose hash function.
+For more details see the [link hash.rationale rationale].
+]
+
+
 [endsect]
 
diff --git a/doc/rationale.qbk b/doc/rationale.qbk
new file mode 100644
index 0000000..8323dfa
--- /dev/null
+++ b/doc/rationale.qbk
@@ -0,0 +1,55 @@
+
+[/ Copyright 2011 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) ]
+
+[section:rationale Rationale]
+
+The rationale for the design can be found in the original design
+[footnote issue 6.18 of the __issues__ (page 63)], but an issue that
+occasionally comes up is the quality of the hash function, so that
+demands some more attention.
+
+Many hash functions strive to have little correlation between the input
+and output values. They attempt to uniformally distribute the output
+values for very similar inputs. This hash function makes no such
+attempt. In fact, for integers, the result of the hash function is often
+just the input value. So similar but different input values will result
+in similar but different output values.
+
+This means that it is not appropriate as a general hash function. For
+example, a hash table may discard bits from the hash function resulting
+in likely collisions, or might have poor collision resolution when hash
+values are clustered together. In such cases this hash function will
+preform poorly.
+
+So why not implement a higher quality hash function? Well, the standard
+makes no such guarantee, it just requires that the hashes of two
+different values are unlikely to collide. So containers or algorithms
+designed to work with the standard hash function will have to be
+implemented to work well when the hash function's output is correlated
+to its input. Since they are paying that cost it would be wasteful to
+expand the effort to make a higher quality hash function.
+
+If you do need a higher quality hash function, there are several options
+available. One is to use a second hash on the output of this hash
+function, such as [@http://www.concentric.net/~ttwang/tech/inthash.htm
+Thomas Wang's hash function]. But for many types this might not work as
+well as a hash algorithm tailored for the input.
+
+For strings that are several fast, high quality hash functions
+available, such as:
+
+* [@http://burtleburtle.net/bob/hash/index.html Bob Jenkins' hash
+  functions]
+* [@http://www.azillionmonkeys.com/qed/hash.html Paul Hsieh's hash
+  functions]
+* [@http://code.google.com/p/cityhash/ Google's CityHash]
+* [@http://code.google.com/p/smhasher/ MurmurHash3]
+
+These may also be appropriate for hashing a binary representation of
+your data - providing that all equal values have an equal
+representation, which is not always the case (e.g. for floating point
+values).
+
+[endsect]
\ No newline at end of file

From 335930c652aab7fc412ed34a499fd07c0f945dac Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 9 Oct 2011 18:22:11 +0000
Subject: [PATCH 18/22] Hash: Remove info for compilers that are no longer
 supported.

[SVN r74857]
---
 doc/portability.qbk | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/doc/portability.qbk b/doc/portability.qbk
index fabb298..a65bc19 100644
--- a/doc/portability.qbk
+++ b/doc/portability.qbk
@@ -90,16 +90,4 @@ boost namespace:
 Full code for this example is at
 [@boost:/libs/functional/hash/examples/portable.cpp /libs/functional/hash/examples/portable.cpp].
 
-[h2 Other Issues]
-
-On Visual C++ versions 6.5 and 7.0, `hash_value` isn't overloaded for built in
-arrays. __boost_hash__, [funcref boost::hash_combine] and [funcref boost::hash_range] all use a workaround to
-support built in arrays so this shouldn't be a problem in most cases.
-
-On Visual C++ versions 6.5 and 7.0, function pointers aren't currently supported.
-
-When using GCC on Solaris, `boost::hash_value(long double)` treats
-`long double`s as `double`s - so the hash function doesn't take into account the
-full range of values.
-
 [endsect]

From 56293f43135d2e44e0babbb73240838a5f7b9d1d Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 16 Oct 2011 10:32:12 +0000
Subject: [PATCH 19/22] Hash: A few edits to the new rationale.

[SVN r74963]
---
 doc/rationale.qbk | 27 +++++++++++----------------
 1 file changed, 11 insertions(+), 16 deletions(-)

diff --git a/doc/rationale.qbk b/doc/rationale.qbk
index 8323dfa..f01605b 100644
--- a/doc/rationale.qbk
+++ b/doc/rationale.qbk
@@ -14,8 +14,8 @@ Many hash functions strive to have little correlation between the input
 and output values. They attempt to uniformally distribute the output
 values for very similar inputs. This hash function makes no such
 attempt. In fact, for integers, the result of the hash function is often
-just the input value. So similar but different input values will result
-in similar but different output values.
+just the input value. So similar but different input values will often
+result in similar but different output values.
 
 This means that it is not appropriate as a general hash function. For
 example, a hash table may discard bits from the hash function resulting
@@ -25,28 +25,23 @@ preform poorly.
 
 So why not implement a higher quality hash function? Well, the standard
 makes no such guarantee, it just requires that the hashes of two
-different values are unlikely to collide. So containers or algorithms
+different values are unlikely to collide. Containers or algorithms
 designed to work with the standard hash function will have to be
 implemented to work well when the hash function's output is correlated
-to its input. Since they are paying that cost it would be wasteful to
-expand the effort to make a higher quality hash function.
+to its input. Since they are paying that cost a higher quality hash function
+would be wasteful.
 
-If you do need a higher quality hash function, there are several options
+For other use cases, if you do need a higher quality hash function,
+there are several options
 available. One is to use a second hash on the output of this hash
 function, such as [@http://www.concentric.net/~ttwang/tech/inthash.htm
-Thomas Wang's hash function]. But for many types this might not work as
+Thomas Wang's hash function]. This this may not work as
 well as a hash algorithm tailored for the input.
 
 For strings that are several fast, high quality hash functions
-available, such as:
-
-* [@http://burtleburtle.net/bob/hash/index.html Bob Jenkins' hash
-  functions]
-* [@http://www.azillionmonkeys.com/qed/hash.html Paul Hsieh's hash
-  functions]
-* [@http://code.google.com/p/cityhash/ Google's CityHash]
-* [@http://code.google.com/p/smhasher/ MurmurHash3]
-
+available (for example [@http://code.google.com/p/smhasher/ MurmurHash3]
+and [@http://code.google.com/p/cityhash/ Google's CityHash]),
+although they tend to be more machine specific.
 These may also be appropriate for hashing a binary representation of
 your data - providing that all equal values have an equal
 representation, which is not always the case (e.g. for floating point

From d92209d725db2884530b394b33798ea41a1cf791 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Fri, 18 Nov 2011 09:02:47 +0000
Subject: [PATCH 20/22] Hash: Use quickbook 1.5

[SVN r75541]
---
 doc/hash.qbk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/hash.qbk b/doc/hash.qbk
index fe428f3..cdb72d4 100644
--- a/doc/hash.qbk
+++ b/doc/hash.qbk
@@ -1,5 +1,5 @@
 [library Boost.Functional/Hash
-    [quickbook 1.4]
+    [quickbook 1.5]
     [authors [James, Daniel]]
     [copyright 2005 2006 2007 2008 Daniel James]
     [purpose A TR1 hash function object that can be extended to hash user

From eb040cb89b253289910f690ec2a9a3f064c05616 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Fri, 18 Nov 2011 09:03:29 +0000
Subject: [PATCH 21/22] Hash: Improve rationale slightly.

[SVN r75542]
---
 doc/rationale.qbk | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/doc/rationale.qbk b/doc/rationale.qbk
index f01605b..273392f 100644
--- a/doc/rationale.qbk
+++ b/doc/rationale.qbk
@@ -5,10 +5,10 @@
 
 [section:rationale Rationale]
 
-The rationale for the design can be found in the original design
-[footnote issue 6.18 of the __issues__ (page 63)], but an issue that
-occasionally comes up is the quality of the hash function, so that
-demands some more attention.
+The rationale can be found in the original design
+[footnote issue 6.18 of the __issues__ (page 63)].
+
+[heading:quality Quality of the hash function]
 
 Many hash functions strive to have little correlation between the input
 and output values. They attempt to uniformally distribute the output
@@ -16,23 +16,23 @@ values for very similar inputs. This hash function makes no such
 attempt. In fact, for integers, the result of the hash function is often
 just the input value. So similar but different input values will often
 result in similar but different output values.
-
 This means that it is not appropriate as a general hash function. For
 example, a hash table may discard bits from the hash function resulting
 in likely collisions, or might have poor collision resolution when hash
 values are clustered together. In such cases this hash function will
 preform poorly.
 
-So why not implement a higher quality hash function? Well, the standard
-makes no such guarantee, it just requires that the hashes of two
-different values are unlikely to collide. Containers or algorithms
+But the standard has no such requirement for the hash function,
+it just requires that the hashes of two different values are unlikely
+to collide. Containers or algorithms
 designed to work with the standard hash function will have to be
 implemented to work well when the hash function's output is correlated
 to its input. Since they are paying that cost a higher quality hash function
 would be wasteful.
 
 For other use cases, if you do need a higher quality hash function,
-there are several options
+then neither the standard hash function or `boost::hash` are appropriate.
+There are several options
 available. One is to use a second hash on the output of this hash
 function, such as [@http://www.concentric.net/~ttwang/tech/inthash.htm
 Thomas Wang's hash function]. This this may not work as
@@ -47,4 +47,4 @@ your data - providing that all equal values have an equal
 representation, which is not always the case (e.g. for floating point
 values).
 
-[endsect]
\ No newline at end of file
+[endsect]

From a6f8c51afbf5b73e23c68f33e1e3474e897624ea Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Thu, 26 Jan 2012 08:17:11 +0000
Subject: [PATCH 22/22] Hash: Fix 1.6 quickbook in 1.5 document.

[SVN r76703]
---
 doc/rationale.qbk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/rationale.qbk b/doc/rationale.qbk
index 273392f..ab03d8b 100644
--- a/doc/rationale.qbk
+++ b/doc/rationale.qbk
@@ -8,7 +8,7 @@
 The rationale can be found in the original design
 [footnote issue 6.18 of the __issues__ (page 63)].
 
-[heading:quality Quality of the hash function]
+[heading Quality of the hash function]
 
 Many hash functions strive to have little correlation between the input
 and output values. They attempt to uniformally distribute the output