Merge pull request #19 from joto/patch-1

fix typo

.travis.yml

@@ -0,0 +1,107 @@
+# Use, modification, and distribution are
+# 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)
+#
+# Copyright Antony Polukhin 2014-2015.
+
+#
+# See https://svn.boost.org/trac/boost/wiki/TravisCoverals for description of this file
+# and how it can be used with Boost libraries.
+#
+# File revision #5
+
+sudo: false
+language: cpp
+compiler:
+    - gcc
+#    - clang
+
+os:
+    - linux
+
+env:
+    global:
+        # Autodetect Boost branch by using the following code: - BRANCH_TO_TEST=$TRAVIS_BRANCH
+        # or just directly specify it
+        - BRANCH_TO_TEST=$TRAVIS_BRANCH
+
+        # Files, which coverage results must be ignored (files from other projects).
+        # Example: - IGNORE_COVERAGE='*/boost/progress.hpp */filesystem/src/*'
+        - IGNORE_COVERAGE=''
+
+        # Explicitly remove the following library from Boost. This may be usefull, if you're for example running Travis
+        # from `Boost.DLL` repo, while Boost already has `dll`.
+        #
+        # By default is eaual to - BOOST_REMOVE=$(basename $TRAVIS_BUILD_DIR)
+        # This will force to use local repo content, instead of the Boost's default.
+        - BOOST_REMOVE=$(basename $TRAVIS_BUILD_DIR)
+
+    matrix:
+        - CXX_STANDARD=c++98
+        - CXX_STANDARD=c++0x
+
+###############################################################################################################
+# From this point and below code is same for all the Boost libs
+###############################################################################################################
+
+
+# Installing additional tools
+addons:
+  apt:
+    packages:
+    - valgrind
+    - python-yaml
+    - lcov
+
+before_install:
+    # Set this to the name of the library
+    - PROJECT_TO_TEST=`basename $TRAVIS_BUILD_DIR`
+    # Cloning Boost libraries (fast nondeep cloning)
+    - BOOST=$HOME/boost-local
+    - echo "Testing $PROJECT_TO_TEST, to remove $BOOST/libs/$BOOST_REMOVE, testing branch $BRANCH_TO_TEST"
+    - git init $BOOST
+    - cd $BOOST
+    - git remote add --no-tags -t $BRANCH_TO_TEST origin https://github.com/boostorg/boost.git
+    - git fetch --depth=1
+    - git checkout $BRANCH_TO_TEST
+    - git submodule update --init --merge
+    - git remote set-branches --add origin $BRANCH_TO_TEST
+    - git pull --recurse-submodules
+    - git submodule update --init
+    - git checkout $BRANCH_TO_TEST
+    - git submodule foreach "git reset --quiet --hard; git clean -fxd"
+    - git reset --hard; git clean -fxd
+    - git status
+    - rm -rf $BOOST/libs/$BOOST_REMOVE
+    - mv $TRAVIS_BUILD_DIR $BOOST/libs/$PROJECT_TO_TEST
+    - TRAVIS_BUILD_DIR=$BOOST/libs/$PROJECT_TO_TEST
+    - ./bootstrap.sh
+    - ./b2 headers
+    - cd $BOOST/libs/$PROJECT_TO_TEST/test/
+
+script:
+    # `--coverage` flags required to generate coverage info for Coveralls
+    - ../../../b2 testing.launcher=valgrind address-model=64 architecture=x86 toolset=$CC cxxflags="--coverage -DBOOST_TRAVISCI_BUILD -std=$CXX_STANDARD" linkflags="--coverage"
+
+after_success:
+    # Copying Coveralls data to a separate folder
+    - mkdir -p $TRAVIS_BUILD_DIR/coverals
+    - find ../../../bin.v2/ -name "*.gcda" -exec cp "{}" $TRAVIS_BUILD_DIR/coverals/ \;
+    - find ../../../bin.v2/ -name "*.gcno" -exec cp "{}" $TRAVIS_BUILD_DIR/coverals/ \;
+
+    # Preparing Coveralls data by changind data format to a readable one
+    - lcov --directory $TRAVIS_BUILD_DIR/coverals --base-directory ./ --capture --output-file $TRAVIS_BUILD_DIR/coverals/coverage.info
+
+    # ... erasing /test/ /example/ folder data
+    - cd $BOOST
+    - lcov --remove $TRAVIS_BUILD_DIR/coverals/coverage.info "/usr*" "*/$PROJECT_TO_TEST/test/*" $IGNORE_COVERAGE "*/$PROJECT_TO_TEST/tests/*" "*/$PROJECT_TO_TEST/examples/*" "*/$PROJECT_TO_TEST/example/*" -o $TRAVIS_BUILD_DIR/coverals/coverage.info
+
+    # ... erasing data that is not related to this project directly
+    - OTHER_LIBS=`grep "submodule .*" .gitmodules | sed 's/\[submodule\ "\(.*\)"\]/"\*\/boost\/\1\.hpp" "\*\/boost\/\1\/\*"/g'| sed "/\"\*\/boost\/$PROJECT_TO_TEST\/\*\"/d" | sed ':a;N;$!ba;s/\n/ /g'`
+    - echo $OTHER_LIBS
+    - eval "lcov --remove $TRAVIS_BUILD_DIR/coverals/coverage.info $OTHER_LIBS -o $TRAVIS_BUILD_DIR/coverals/coverage.info"
+
+    # Sending data to Coveralls
+    - cd $TRAVIS_BUILD_DIR
+    - gem install coveralls-lcov
+    - coveralls-lcov coverals/coverage.info

README.md

@@ -0,0 +1,16 @@
+#[Boost.Variant](http://boost.org/libs/variant)
+Boost.Variant, part of collection of the [Boost C++ Libraries](http://github.com/boostorg). It is a safe, generic, stack-based discriminated union container, offering a simple solution for manipulating an object from a heterogeneous set of types in a uniform manner.
+
+### Test results
+
+@               | Build         | Tests coverage | More info
+----------------|-------------- | -------------- |-----------
+Develop branch: | [![Build Status](https://travis-ci.org/apolukhin/variant.svg?branch=develop)](https://travis-ci.org/apolukhin/variant)  | [![Coverage Status](https://coveralls.io/repos/apolukhin/variant/badge.png?branch=develop)](https://coveralls.io/r/apolukhin/variant?branch=develop) | [details...](http://www.boost.org/development/tests/develop/developer/variant.html)
+Master branch:  | [![Build Status](https://travis-ci.org/apolukhin/variant.svg?branch=master)](https://travis-ci.org/apolukhin/variant)  | [![Coverage Status](https://coveralls.io/repos/apolukhin/variant/badge.png?branch=master)](https://coveralls.io/r/apolukhin/variant?branch=master) | [details...](http://www.boost.org/development/tests/master/developer/variant.html)
+
+
+[Open Issues](https://svn.boost.org/trac/boost/query?status=!closed&component=variant)
+
+### License
+
+Distributed under the [Boost Software License, Version 1.0](http://boost.org/LICENSE_1_0.txt).

doc/Jamfile.v2

@@ -1,4 +1,13 @@
-project boost/doc ;
+#  Boost.Variant Library doc Jamfile
+#
+#  Copyright (C) 2003, Eric Friedman, Itay Maman.
+#
+# 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)
+#
+
+project variant/doc ;
 import boostbook : boostbook ;
 
 boostbook variant-doc 

doc/biblio.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE section PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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 id="variant.refs">
   <title>References</title>
 
@@ -109,4 +115,4 @@
     2002.
 </para>
 
-</section>
+</section>

doc/design.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE section PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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 id="variant.design">
   <title>Design Overview</title>
 
@@ -270,29 +276,6 @@
 
       </para>
 
-      <para><emphasis role="bold">Caveat</emphasis>: On most platforms, the
-        <libraryname>Type Traits</libraryname> templates
-        <code>has_nothrow_copy</code> and <code>has_nothrow_constructor</code>
-        by default return <code>false</code> for all <code>class</code> and
-        <code>struct</code> types. It is necessary therefore to provide
-        specializations of these templates as appropriate for user-defined
-        types, as demonstrated in the following:
-
-<programlisting>// ...in your code (at file scope)...
-
-namespace boost {
-
-  template &lt;&gt;
-  struct <classname>has_nothrow_copy</classname>&lt; myUDT &gt;
-    : <classname>mpl::true_</classname>
-  {
-  };
-
-}
-</programlisting>
-
-      </para>
-
       <para><emphasis role="bold">Implementation Note</emphasis>: So as to make
         the behavior of <code>variant</code> more predictable in the aftermath
         of an exception, the current implementation prefers to default-construct
@@ -324,4 +307,4 @@ namespace boost {
 
   </section>
 
-</section>
+</section>

doc/introduction.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE section PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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 id="variant.intro">
   <title>Introduction</title>
 
@@ -132,4 +138,4 @@ int main()
 
 </section>
 
-</section>
+</section>

doc/misc.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE section PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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 id="variant.misc">
   <title>Miscellaneous Notes</title>
 
@@ -232,4 +238,4 @@ interface, and implementation of the library.</para>
 
 </section>
 
-</section>
+</section>

doc/reference/apply_visitor.xml

@@ -1,6 +1,13 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+    Copyright 2013-2014 Antony Polukhin.
+
+    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)
+-->
 <header name="boost/variant/apply_visitor.hpp">
   <namespace name="boost">
     <class name="apply_visitor_delayed_t">
@@ -14,6 +21,9 @@
         <simpara>See the &quot;visitor-only&quot; form of
           <code><functionname>apply_visitor</functionname></code> for a simple
           way to create <code>apply_visitor_delayed_t</code> objects.</simpara>
+        <simpara>See <code><classname>apply_visitor_delayed_cpp14_t</classname></code>
+            which is used on C++14 compatible compilers when <code>Visitor</code> has no
+            <code>result_type</code> typedef.</simpara>
       </description>
 
       <template>
@@ -37,6 +47,18 @@
 
       <method-group name="function object interface">
         <overloaded-method name="operator()">
+          <signature>
+            <template>
+              <template-type-parameter name="... Variant"/>
+            </template>
+
+            <type>result_type</type>
+            <parameter name="operand">
+              <paramtype>Variant&amp;...</paramtype>
+            </parameter>
+          </signature>
+
+
           <signature>
             <template>
               <template-type-parameter name="Variant"/>
@@ -69,10 +91,69 @@
             <code><functionname>apply_visitor</functionname></code> on the
             stored visitor using the given operands.</simpara>
           </description>
+          <notes>Version with variadic templates is used by default if
+          <macroname>BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</macroname> is not defined.</notes>
         </overloaded-method>
       </method-group>
     </class>
-  
+
+    <class name="apply_visitor_delayed_cpp14_t">
+      <purpose>Adapts a visitor for use as a function object.</purpose>
+      <description>
+        <simpara>Adapts the function given at construction for use as a
+          function object. This is useful, for example, when one needs to
+          operate on each element of a sequence of variant objects using a
+          standard library algorithm such as
+          <code>std::for_each</code>.</simpara>
+        <simpara>See the &quot;visitor-only&quot; form of
+          <code><functionname>apply_visitor</functionname></code> for a simple
+          way to create <code>apply_visitor_delayed_t</code> objects.</simpara>
+        <simpara>See <code><classname>apply_visitor_delayed_t</classname></code>
+            which is used when <code>Visitor</code> has <code>result_type</code>
+            typedef.</simpara>
+        <simpara>Available only if macro
+          <macroname>BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</macroname> is not defined and
+          compiler supports <code>decltype(auto)</code> and <code>decltype(some-expression)</code>.</simpara>
+      </description>
+
+      <template>
+        <template-type-parameter name="Visitor"/>
+      </template>
+
+      <constructor specifiers="explicit">
+        <parameter name="visitor">
+          <paramtype>Visitor &amp;</paramtype>
+        </parameter>
+
+        <effects>
+          <simpara>Constructs the function object with the given
+            visitor.</simpara>
+        </effects>
+      </constructor>
+
+      <method-group name="function object interface">
+        <overloaded-method name="operator()">
+          <signature>
+            <template>
+              <template-type-parameter name="... Variant"/>
+            </template>
+
+            <type>decltype(auto)</type>
+            <parameter name="operand">
+              <paramtype>Variant&amp;...</paramtype>
+            </parameter>
+          </signature>
+
+          <purpose>Function call operator.</purpose>
+          <description>
+            <simpara>Invokes
+            <code><functionname>apply_visitor</functionname></code> on the
+            stored visitor using the given operands.</simpara>
+          </description>
+        </overloaded-method>
+      </method-group>
+    </class>
+
     <overloaded-function name="apply_visitor">
       <signature>
         <template>
@@ -89,7 +170,7 @@
           <paramtype>Variant &amp;</paramtype>
         </parameter>
       </signature>
-      
+
       <signature>
         <template>
           <template-type-parameter name="Visitor"/>
@@ -113,7 +194,7 @@
           <template-type-parameter name="Variant2"/>
         </template>
 
-        <type>typename BinaryVisitor::result_type</type>
+        <type>typename BinaryVisitor::result_type OR decltype(auto)</type>
 
         <parameter name="visitor">
           <paramtype>BinaryVisitor &amp;</paramtype>
@@ -133,7 +214,7 @@
           <template-type-parameter name="Variant2"/>
         </template>
 
-        <type>typename BinaryVisitor::result_type</type>
+        <type>typename BinaryVisitor::result_type OR decltype(auto)</type>
 
         <parameter name="visitor">
           <paramtype>const BinaryVisitor &amp;</paramtype>
@@ -154,7 +235,7 @@
           <template-type-parameter name="Variant3"/>
         </template>
 
-        <type>typename MultiVisitor::result_type</type>
+        <type>typename MultiVisitor::result_type OR decltype(auto)</type>
 
         <parameter name="visitor">
           <paramtype>MultiVisitor &amp;</paramtype>
@@ -181,7 +262,7 @@
           <template-type-parameter name="Variant3"/>
         </template>
 
-        <type>typename MultiVisitor::result_type</type>
+        <type>typename MultiVisitor::result_type OR decltype(auto)</type>
 
         <parameter name="visitor">
           <paramtype>const MultiVisitor &amp;</paramtype>
@@ -212,6 +293,19 @@
         </parameter>
       </signature>
 
+
+      <signature>
+        <template>
+          <template-type-parameter name="Visitor"/>
+        </template>
+
+        <type><classname>apply_visitor_delayed_cpp14_t</classname>&lt;Visitor&gt;</type>
+
+        <parameter name="visitor">
+          <paramtype>Visitor &amp;</paramtype>
+        </parameter>
+      </signature>
+
       <purpose>
         <simpara>Allows compile-time checked type-safe application of the
         given visitor to the content of the given variant, ensuring that all
@@ -236,13 +330,17 @@
             <listitem>Overloads accepting three or more operands invoke the
               function call operator of the given visitor on the content of
               the given <code><classname>variant</classname></code>
-              operands. Maximum amount of parameters controlled by 
+              operands. Maximum amount of parameters controlled by
               <code><emphasis role="bold"><macroname>BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS</macroname></emphasis></code>
-              macro. Those functions are actually defined in <xref linkend="header.boost.variant.multivisitors_hpp"/>.</listitem>
+              macro. Those functions are actually defined in a header <code>boost/variant/multivisitors.hpp</code>
+              (See <xref linkend="header.boost.variant.multivisitors_hpp"/>). That header must be manually included
+              if multi visitors are meant for use.</listitem>
 
-            <listitem>The overload accepting only a visitor returns a
-              <classname alt="boost::apply_visitor_delayed_t">generic function object</classname>
-              that accepts either one or two arguments and invokes
+            <listitem>The overloads accepting only a visitor return a
+              <classname alt="boost::apply_visitor_delayed_t">C++03 compatible generic function object</classname>
+              or
+                <classname alt="boost::apply_visitor_delayed_cpp14_t">C++14 compatible generic function object</classname>
+              that accepts either one, two or arbitrary count of arguments and invoke
               <code><functionname>apply_visitor</functionname></code> using
               these arguments and <code>visitor</code>, thus behaving as
               specified above. (This behavior is particularly useful, for

doc/reference/bad_visit.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/bad_visit.hpp">
   <namespace name="boost">
 
@@ -20,4 +26,4 @@
     </class>
 
   </namespace>
-</header>
+</header>

doc/reference/concepts.xml

@@ -1,4 +1,12 @@
-<?xml version="1.0" encoding="utf-8" ?> 
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
+  "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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 id="variant.concepts">
   <title>Concepts</title>
 
@@ -74,7 +82,9 @@
       <listitem>Must allow invocation as a function by overloading
         <code>operator()</code>, unambiguously accepting any value of type
         <code>T</code>.</listitem>
-      <listitem>Must expose inner type <code>result_type</code>. (See 
+      <listitem>Must expose inner type <code>result_type</code>. C++14 compatible compilers
+        could detect <code>result_type</code> automatically, but will stick to
+        <code>result_type</code> if it is defined. (See 
         <code><functionname>boost::visitor_ptr</functionname></code> for a
         solution to using functions as visitors.)</listitem>
       <listitem>If <code>result_type</code> is not <code>void</code>, then
@@ -123,6 +133,18 @@ public:
     }
 };</programlisting>
 
+      <para>C++14 compatible compilers detect <code>result_type</code> automatically:</para>
+
+<programlisting>
+    <classname>boost::variant</classname>&lt;int, float&gt; v;
+    // ...
+
+    <functionname>boost::apply_visitor</functionname>(
+        [](auto val) { return std::to_string(val); },
+        v
+    );
+</programlisting>
+
     </section>
   </section>
 
@@ -151,4 +173,4 @@ public:
     </itemizedlist>
   </section>
   
-</section>
+</section>

doc/reference/get.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/get.hpp">
   <namespace name="boost">
 
@@ -20,7 +26,7 @@
       </method>
     </class>
 
-    <overloaded-function name="get">
+    <overloaded-function name="relaxed_get">
       <signature>
         <template>
           <template-type-parameter name="U"/>
@@ -52,7 +58,7 @@
           <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
         </parameter>
       </signature>
-      
+
       <signature>
         <template>
           <template-type-parameter name="U"/>
@@ -87,7 +93,9 @@
 
       <purpose>
         <simpara>Retrieves a value of a specified type from a given
-          <code><classname>variant</classname></code>.</simpara>
+          <code><classname>variant</classname></code>. </simpara>
+        <simpara>Unlike <functionname>strict_get</functionname> does not assert at compile time
+        that type <code>U</code> is one of the types that can be stored in variant.</simpara>
       </purpose>
 
       <description>
@@ -96,6 +104,11 @@
           <code><classname>variant</classname></code>. The function succeeds
           only if the content is of the specified type <code>U</code>, with
           failure indicated as described below.</simpara>
+        <simpara><emphasis role="bold">Recomendation</emphasis>: Use
+          <functionname>get</functionname> or <functionname>strict_get</functionname> in new code.
+          <functionname>strict_get</functionname>
+          provides more compile time checks and it's behavior is closer to <code>std::get</code>
+          from C++ Standard Library.</simpara>
         <simpara><emphasis role="bold">Warning</emphasis>: After either
           <code>operand</code> or its content is destroyed (e.g., when the
           given <code><classname>variant</classname></code> is assigned a
@@ -142,5 +155,164 @@
       </rationale>
     </overloaded-function>
 
+    <overloaded-function name="strict_get">
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U *</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U *</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <purpose>
+        <simpara>Retrieves a value of a specified type from a given
+          <code><classname>variant</classname></code>.</simpara>
+      </purpose>
+
+      <description>
+        <simpara>Acts exactly like <functionname>relaxed_get</functionname> but does a compile time check
+        that type <code>U</code> is one of the types that can be stored in variant.</simpara>
+      </description>
+    </overloaded-function>
+
+    <overloaded-function name="get">
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U *</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U *</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <purpose>
+        <simpara>Retrieves a value of a specified type from a given
+          <code><classname>variant</classname></code>.</simpara>
+      </purpose>
+
+      <description>
+        <simpara>Evaluates to <functionname>strict_get</functionname> if <code>BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT</code>
+          is not defined. If <code>BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT</code>
+          is defined then evaluates to <functionname>relaxed_get</functionname>. </simpara>
+
+        <simpara><emphasis role="bold">Recomendation</emphasis>: Use
+          <functionname>get</functionname> in new code without defining
+          <code>BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT</code>. In that way <functionname>get</functionname>
+          provides more compile time checks and it's behavior is closer to <code>std::get</code>
+          from C++ Standard Library.</simpara>
+      </description>
+    </overloaded-function>
+
   </namespace>
 </header>

doc/reference/multivisitor.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2013-2014, Antony Polukhin.
+
+    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)
+-->
 <header name="boost/variant/multivisitors.hpp">
   <using-namespace name="boost"/>
 
@@ -10,7 +16,9 @@
     <macro name="BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS">
       <purpose>
         <simpara>Controls maximum amount of <code><classname>variant</classname></code>
-          parameters for multi visistors. </simpara>
+          parameters for multi visistors. Not used when <code>std::tuple</code> is available and
+          <code><macroname>BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</macroname></code>
+          is not defined.</simpara>
       </purpose>
 
       <description>
@@ -38,7 +46,7 @@
           <template-type-parameter name="Variant3"/>
         </template>
 
-        <type>typename MultiVisitor::result_type</type>
+        <type>typename MultiVisitor::result_type OR decltype(auto)</type>
 
         <parameter name="visitor">
           <paramtype>MultiVisitor &amp;</paramtype>
@@ -65,7 +73,7 @@
           <template-type-parameter name="Variant3"/>
         </template>
 
-        <type>typename MultiVisitor::result_type</type>
+        <type>typename MultiVisitor::result_type OR decltype(auto)</type>
 
         <parameter name="visitor">
           <paramtype>const MultiVisitor &amp;</paramtype>

doc/reference/polymorphic_get.xml

@@ -0,0 +1,326 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
+  "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2013-20014, Antony Polukhin.
+
+    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)
+-->
+<header name="boost/variant/polymorphic_get.hpp">
+  <namespace name="boost">
+
+    <class name="bad_polymorphic_get">
+      <inherit access="public">
+        <classname>boost::bad_get</classname>
+      </inherit>
+
+      <purpose>
+        <simpara>The exception thrown in the event of a failed application of
+        <code><functionname>boost::polymorphic_get</functionname></code> on	the given
+        operand value.</simpara>
+      </purpose>
+
+      <method	name="what"	specifiers="virtual" cv="const">
+        <type>const	char *</type>
+      </method>
+    </class>
+
+    <overloaded-function name="polymorphic_relaxed_get">
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U *</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U *</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <purpose>
+        <simpara>Retrieves a value of a specified type from a given
+          <code><classname>variant</classname></code>.</simpara>
+        <simpara>Unlike <functionname>polymorphic_strict_get</functionname> does not assert at compile time
+        that type <code>U</code> is one of the types that can be stored in variant.</simpara>
+      </purpose>
+
+      <description>
+        <simpara>The <code>polymorphic_get</code> function allows run-time checked,
+          type-safe retrieval of the content of the given
+          <code><classname>variant</classname></code>. The function succeeds
+          only if the content is of the specified type <code>U</code> or of type
+          derived from type <code>U</code>, with
+          failure indicated as described below.</simpara>
+        <simpara><emphasis role="bold">Recomendation</emphasis>: Use
+          <functionname>polymorphic_get</functionname> or <functionname>polymorphic_strict_get</functionname>
+          in new code.
+          <functionname>polymorphic_strict_get</functionname>
+          provides more compile time checks and it's behavior is closer to <code>std::get</code>
+          from C++ Standard Library.</simpara>
+        <simpara><emphasis role="bold">Warning</emphasis>: After either
+          <code>operand</code> or its content is destroyed (e.g., when the
+          given <code><classname>variant</classname></code> is assigned a
+          value of different type), the returned reference is invalidated.
+          Thus, significant care and caution must be extended when handling
+          the returned reference.</simpara>
+      </description>
+
+      <notes>
+        <simpara>As part of its guarantee of type-safety, <code>polymorphic_get</code>
+        enforces <code>const</code>-correctness. Thus, the specified type
+        <code>U</code> must be <code>const</code>-qualified whenever
+        <code>operand</code> or its content is likewise
+        <code>const</code>-qualified. The converse, however, is not required:
+        that is, the specified type <code>U</code> may be
+        <code>const</code>-qualified even when <code>operand</code> and its
+        content are not.</simpara>
+      </notes>
+
+      <returns>
+        <simpara>If passed a pointer, <code>polymorphic_get</code> returns a pointer to
+        the value content if it is of the specified type <code>U</code> or of type
+        derived from type <code>U</code>;
+        otherwise, a null pointer is returned. If passed a reference,
+        <code>polymorphic_get</code> returns a reference to the value content if it is of
+        the specified type <code>U</code>  or of type
+          derived from type <code>U</code>; otherwise, an exception is thrown
+        (see below).</simpara>
+      </returns>
+
+      <throws>
+        <simpara>Overloads taking a
+        <code><classname>variant</classname></code> pointer will not
+        throw; the overloads taking a
+        <code><classname>variant</classname></code> reference throw
+        <code><classname>bad_polymorphic_get</classname></code> if the content is not of
+        the specified type <code>U</code>or of type
+        derived from type <code>U</code>.</simpara>
+      </throws>
+
+      <rationale>
+        <simpara>While visitation via
+        <code><functionname>apply_visitor</functionname></code>
+        is generally preferred due to its greater safety, <code>polymorphic_get</code> may
+        may be more convenient in some cases due to its straightforward
+        usage.</simpara>
+      </rationale>
+    </overloaded-function>
+
+
+
+    <overloaded-function name="polymorphic_strict_get">
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U *</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U *</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <purpose>
+        <simpara>Retrieves a value of a specified type from a given
+          <code><classname>variant</classname></code>.</simpara>
+      </purpose>
+
+      <description>
+        <simpara>Acts exactly like <functionname>polymorphic_relaxed_get</functionname> but does a compile time check
+        that type <code>U</code> is one of the types that can be stored in variant.</simpara>
+      </description>
+    </overloaded-function>
+
+    <overloaded-function name="polymorphic_get">
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U *</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U *</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; *</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype><classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <signature>
+        <template>
+          <template-type-parameter name="U"/>
+          <template-type-parameter name="T1"/>
+          <template-type-parameter name="T2"/>
+          <template-varargs/>
+          <template-type-parameter name="TN"/>
+        </template>
+
+        <type>const U &amp;</type>
+
+        <parameter name="operand">
+          <paramtype>const <classname>variant</classname>&lt;T1, T2, ..., TN&gt; &amp;</paramtype>
+        </parameter>
+      </signature>
+
+      <purpose>
+        <simpara>Retrieves a value of a specified type from a given
+          <code><classname>variant</classname></code>.</simpara>
+      </purpose>
+
+      <description>
+        <simpara>Evaluates to <functionname>polymorphic_strict_get</functionname>
+          if <code>BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT</code>
+          is not defined. If <code>BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT</code>
+          is defined then evaluates to <functionname>polymorphic_relaxed_get</functionname>. </simpara>
+
+        <simpara><emphasis role="bold">Recomendation</emphasis>: Use
+          <functionname>polymorphic_get</functionname> in new code without defining
+          <code>BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT</code>. In that way
+          <functionname>polymorphic_get</functionname>
+          provides more compile time checks and it's behavior is closer to <code>std::get</code>
+          from C++ Standard Library.</simpara>
+      </description>
+    </overloaded-function>
+  </namespace>
+</header>

doc/reference/recursive_variant.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/recursive_variant.hpp">
   <namespace name="boost">
 
@@ -108,4 +114,4 @@
     </class>
 
   </namespace>
-</header>
+</header>

doc/reference/recursive_wrapper.xml

@@ -1,6 +1,12 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/recursive_wrapper.hpp">
   <namespace name="boost">
 
@@ -261,4 +267,4 @@
     </class>
 
   </namespace>
-</header>
+</header>

doc/reference/reference.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE library-reference PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <library-reference xmlns:xi="http://www.w3.org/2001/XInclude">
 
   <xi:include href="concepts.xml"/>
@@ -19,6 +25,7 @@
   <xi:include href="apply_visitor.xml"/>
   <xi:include href="multivisitor.xml"/>
   <xi:include href="get.xml"/>
+  <xi:include href="polymorphic_get.xml"/>
   <xi:include href="bad_visit.xml"/>
   <xi:include href="static_visitor.xml"/>
   <xi:include href="visitor_ptr.xml"/>

doc/reference/static_visitor.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/static_visitor.hpp">
   <namespace name="boost">
 
@@ -28,4 +34,4 @@
     </class>
 
   </namespace>
-</header>
+</header>

doc/reference/variant.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/variant.hpp">
   <namespace name="boost">
     <class name="variant">
@@ -502,6 +508,12 @@
         <method name="type" cv="const">
           <type>const std::type_info &amp;</type>
 
+          <notes>
+            <simpara><code>boost::variant</code> usues Boost.TypeIndex library so actually
+            <code>const boost::typeindex::type_info &amp;</code> is returned.
+            This method is available even if RTTI is off.</simpara>
+          </notes>
+
           <returns>
             <simpara><code>typeid(x)</code>, where <code>x</code> is the the
               content of <code>*this</code>.</simpara>
@@ -509,10 +521,6 @@
 
           <throws>Will not throw.</throws>
           
-          <notes>
-            <simpara>Not available when <code>BOOST_NO_TYPEID</code> is
-              defined.</simpara>
-          </notes>
         </method>
 
       </method-group>
@@ -528,7 +536,7 @@
               <paramtype>const variant &amp;</paramtype>
             </parameter>
           </signature>
-          
+
           <signature cv="const">
             <type>void</type>
             <template>
@@ -554,14 +562,60 @@
           </requires>
 
           <returns>
-            <simpara><code>true</code> iff <code>which() == rhs.which()</code>
+            <simpara><code>true</code> if <code>which() == rhs.which()</code>
               <emphasis>and</emphasis>
               <code>content_this == content_rhs</code>, where
               <code>content_this</code> is the content of <code>*this</code>
               and <code>content_rhs</code> is the content of
               <code>rhs</code>.</simpara>
           </returns>
-          
+
+          <throws>
+            <simpara>If <code>which() == rhs.which()</code> then may fail with
+              any exceptions arising from <code>operator==(T,T)</code>, where
+              <code>T</code> is the contained type of
+              <code>*this</code>.</simpara>
+          </throws>
+        </overloaded-method>
+
+        <overloaded-method name="operator!=" cv="const">
+          <purpose>InEquality comparison.</purpose>
+
+          <signature cv="const">
+            <type>bool</type>
+            <parameter name="rhs">
+              <paramtype>const variant &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <signature cv="const">
+            <type>void</type>
+            <template>
+              <template-type-parameter name="U"/>
+            </template>
+            <parameter>
+              <paramtype>const U &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <notes>
+            <simpara>The overload returning <code>void</code> exists only to
+              prohibit implicit conversion of the operator's right-hand side
+              to <code>variant</code>; thus, its use will (purposefully)
+              result in a compile-time error.</simpara>
+          </notes>
+
+          <requires>
+            <simpara>Every bounded type of the <code>variant</code> must
+              fulfill the requirements of the
+              <conceptname>EqualityComparable</conceptname>
+              concept.</simpara>
+          </requires>
+
+          <returns>
+            <simpara><code>true</code> if <code>!(*this == rhs)</code>.</simpara>
+          </returns>
+
           <throws>
             <simpara>If <code>which() == rhs.which()</code> then may fail with
               any exceptions arising from <code>operator==(T,T)</code>, where
@@ -579,7 +633,7 @@
               <paramtype>const variant &amp;</paramtype>
             </parameter>
           </signature>
-          
+
           <signature cv="const">
             <type>void</type>
             <template>
@@ -620,6 +674,147 @@
           </throws>
         </overloaded-method>
 
+
+        <overloaded-method name="operator&gt;">
+          <purpose>GreaterThan comparison.</purpose>
+
+          <signature cv="const">
+            <type>bool</type>
+            <parameter name="rhs">
+              <paramtype>const variant &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <signature cv="const">
+            <type>void</type>
+            <template>
+              <template-type-parameter name="U"/>
+            </template>
+            <parameter>
+              <paramtype>const U &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <notes>
+            <simpara>The overload returning <code>void</code> exists only to
+              prohibit implicit conversion of the operator's right-hand side
+              to <code>variant</code>; thus, its use will (purposefully)
+              result in a compile-time error.</simpara>
+          </notes>
+
+          <requires>
+            <simpara>Every bounded type of the <code>variant</code> must
+              fulfill the requirements of the
+              <conceptname>LessThanComparable</conceptname>
+              concept.</simpara>
+          </requires>
+
+          <returns>
+            <simpara>true if <code>rhs &lt; *this</code>.</simpara>
+          </returns>
+
+          <throws>
+            <simpara>May fail with
+              any exceptions arising from <code>operator&lt;(T,T)</code>,
+              where <code>T</code> is the contained type of
+              <code>*this</code>.</simpara>
+          </throws>
+        </overloaded-method>
+
+
+        <overloaded-method name="operator&lt;=">
+          <purpose>LessThan or Equal comparison.</purpose>
+
+          <signature cv="const">
+            <type>bool</type>
+            <parameter name="rhs">
+              <paramtype>const variant &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <signature cv="const">
+            <type>void</type>
+            <template>
+              <template-type-parameter name="U"/>
+            </template>
+            <parameter>
+              <paramtype>const U &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <notes>
+            <simpara>The overload returning <code>void</code> exists only to
+              prohibit implicit conversion of the operator's right-hand side
+              to <code>variant</code>; thus, its use will (purposefully)
+              result in a compile-time error.</simpara>
+          </notes>
+
+          <requires>
+            <simpara>Every bounded type of the <code>variant</code> must
+              fulfill the requirements of the
+              <conceptname>LessThanComparable</conceptname>
+              concept.</simpara>
+          </requires>
+
+          <returns>
+            <simpara>true if <code>!(*this > rhs)</code>.</simpara>
+          </returns>
+
+          <throws>
+            <simpara>May fail with
+              any exceptions arising from <code>operator&lt;(T,T)</code>,
+              where <code>T</code> is the contained type of
+              <code>*this</code>.</simpara>
+          </throws>
+        </overloaded-method>
+
+
+        <overloaded-method name="operator&gt;=">
+          <purpose>GreaterThan or Equal comparison.</purpose>
+
+          <signature cv="const">
+            <type>bool</type>
+            <parameter name="rhs">
+              <paramtype>const variant &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <signature cv="const">
+            <type>void</type>
+            <template>
+              <template-type-parameter name="U"/>
+            </template>
+            <parameter>
+              <paramtype>const U &amp;</paramtype>
+            </parameter>
+          </signature>
+
+          <notes>
+            <simpara>The overload returning <code>void</code> exists only to
+              prohibit implicit conversion of the operator's right-hand side
+              to <code>variant</code>; thus, its use will (purposefully)
+              result in a compile-time error.</simpara>
+          </notes>
+
+          <requires>
+            <simpara>Every bounded type of the <code>variant</code> must
+              fulfill the requirements of the
+              <conceptname>LessThanComparable</conceptname>
+              concept.</simpara>
+          </requires>
+
+          <returns>
+            <simpara>true if <code>!(*this &lt; lhs)</code>.</simpara>
+          </returns>
+
+          <throws>
+            <simpara>May fail with
+              any exceptions arising from <code>operator&lt;(T,T)</code>,
+              where <code>T</code> is the contained type of
+              <code>*this</code>.</simpara>
+          </throws>
+        </overloaded-method>
+
       </method-group>
     </class>
 

doc/reference/variant_fwd.xml

@@ -1,4 +1,12 @@
-<?xml version="1.0" encoding="utf-8" ?> 
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
+  "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/variant_fwd.hpp">
   <using-namespace name="boost"/>
 
@@ -14,7 +22,10 @@
     <purpose>
       <simpara>Expands to the length of the
         template parameter list for
-        <code><classname>variant</classname></code>.</simpara>
+        <code><classname>variant</classname></code>. Not used if
+        <code><macroname>BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</macroname></code>
+        is not defined. 
+      </simpara>
     </purpose>
 
     <description>
@@ -25,6 +36,18 @@
     </description>
   </macro>
 
+  <macro name="BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES">
+    <purpose>
+      <simpara>If this macro is defined, then library won't use C++11 variadic templates.
+        Users may define this macro to make 
+        <code><macroname>BOOST_VARIANT_ENUM_PARAMS</macroname></code>
+        and <code><macroname>BOOST_VARIANT_ENUM_SHIFTED_PARAMS</macroname></code> expand
+        to a comma-separated sequence instead of variadic templates. Define this macro if
+        your compiler has problems with compilation of variadic templates.
+      </simpara>
+    </purpose>
+  </macro>
+
   <macro name="BOOST_VARIANT_ENUM_PARAMS" kind="functionlike">
     <macro-parameter name="param"/>
 
@@ -34,7 +57,21 @@
     </purpose>
 
     <description>
-      <para>Expands to a comma-separated sequence of length
+      <para> When variadic templates are available and
+        <code><macroname>BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</macroname></code>
+        is not defined, expands to variadic template list in the following manner:
+        <code><programlisting>
+            BOOST_VARIANT_ENUM_PARAMS(T)                    => T0, TN...
+            BOOST_VARIANT_ENUM_PARAMS(class T)              => class T0, class... TN
+            BOOST_VARIANT_ENUM_PARAMS(class Something)      => class Something0, class... SomethingN
+            BOOST_VARIANT_ENUM_PARAMS(typename Something)   => typename Something0, typename... SomethingN
+            BOOST_VARIANT_ENUM_PARAMS(Something)            => Something0, SomethingN...
+            BOOST_VARIANT_ENUM_PARAMS(Something)            => Something0, SomethingN...
+        </programlisting></code>
+      </para>
+
+      <para>
+        Otherwise expands to a comma-separated sequence of length
         <code><macroname>BOOST_VARIANT_LIMIT_TYPES</macroname></code>, where
         each element in the sequence consists of the concatenation of
         <emphasis>param</emphasis> with its zero-based index into the
@@ -59,7 +96,21 @@
     </purpose>
 
     <description>
-      <para>Expands to a comma-separated sequence of length
+      <para> When variadic templates are available and
+        <code><macroname>BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</macroname></code>
+        is not defined, expands to variadic template list in the following manner:
+        <code><programlisting>
+            BOOST_VARIANT_ENUM_SHIFTED_PARAMS(T)                    => TN...
+            BOOST_VARIANT_ENUM_SHIFTED_PARAMS(class T)              => class... TN
+            BOOST_VARIANT_ENUM_SHIFTED_PARAMS(class Something)      => class... SomethingN
+            BOOST_VARIANT_ENUM_SHIFTED_PARAMS(typename Something)   => typename... SomethingN
+            BOOST_VARIANT_ENUM_SHIFTED_PARAMS(Something)            => SomethingN...
+            BOOST_VARIANT_ENUM_SHIFTED_PARAMS(Something)            => SomethingN...
+        </programlisting></code>
+      </para>
+
+      <para>
+        Otherwise expands to a comma-separated sequence of length
         <code><macroname>BOOST_VARIANT_LIMIT_TYPES</macroname> - 1</code>,
         where each element in the sequence consists of the concatenation of
         <emphasis>param</emphasis> with its one-based index into the sequence.
@@ -121,4 +172,4 @@
         full lambda support either.)</para>
     </description>
   </macro>
-</header>
+</header>

doc/reference/visitor_ptr.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE header PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <header name="boost/variant/visitor_ptr.hpp">
   <namespace name="boost">
 
@@ -105,4 +111,4 @@
     </function>
 
   </namespace>
-</header>
+</header>

doc/tutorial/advanced.xml

@@ -1,6 +1,13 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+    Copyright 2013-2014, Antony Polukhin.
+
+    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 id="variant.tutorial.advanced">
   <title>Advanced Topics</title>
 
@@ -390,19 +397,20 @@ struct if_visitor: public <classname>boost::static_visitor</classname>&lt;arithm
     arguments by means of <code>apply_visitor</code>:
 
 <programlisting>
-bool_like_t v0(1), v1(true), v2(1.0);
+bool_like_t v0(true), v1(1), v2(2.0);
 
 assert(
     <functionname>boost::apply_visitor</functionname>(if_visitor(), v0, v1, v2)
     ==
-    arithmetics_t(true)
+    arithmetics_t(1)
 );
 </programlisting>
   </para>
 
   <para>Finally, we must note that multi visitation does not support 
     &quot;delayed&quot; form of
-    <code><functionname>apply_visitor</functionname></code>.
+    <code><functionname>apply_visitor</functionname> if
+    <macroname>BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</macroname> is defined</code>.
   </para>
 
 </section>

doc/tutorial/basic.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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 id="variant.tutorial.basic">
   <title>Basic Usage</title>
 

doc/tutorial/tutorial.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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 xmlns:xi="http://www.w3.org/2001/XInclude" id="variant.tutorial">
 
 <title>Tutorial</title>

doc/variant.xml

@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
+<!--
+    Copyright 2003, Eric Friedman, Itay Maman.
+
+    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)
+-->
 <library name="Variant" dirname="variant" 
          xmlns:xi="http://www.w3.org/2001/XInclude" id="variant">
 <libraryinfo>

include/boost/variant/detail/apply_visitor_binary.hpp

@@ -3,8 +3,8 @@
 // See http://www.boost.org for updates, documentation, and revision history.
 //-----------------------------------------------------------------------------
 //
-// Copyright (c) 2002-2003
-// Eric Friedman
+// Copyright (c) 2002-2003 Eric Friedman
+// Copyright (c) 2014 Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
@@ -25,6 +25,11 @@
 #include "boost/type_traits/is_const.hpp"
 #endif
 
+
+#if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+#   include "boost/variant/detail/has_result_type.hpp"
+#endif
+
 namespace boost {
 
 //////////////////////////////////////////////////////////////////////////
@@ -69,7 +74,6 @@ public: // visitor interfaces
 
 private:
     apply_visitor_binary_invoke& operator=(const apply_visitor_binary_invoke&);
-
 };
 
 template <typename Visitor, typename Visitable2>
@@ -173,6 +177,104 @@ apply_visitor(
     return boost::apply_visitor(unwrapper, visitable1);
 }
 
+
+#if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+
+//////////////////////////////////////////////////////////////////////////
+// function template apply_visitor(visitor, visitable1, visitable2)
+//
+// C++14 part.
+//
+
+namespace detail { namespace variant {
+
+template <typename Visitor, typename Value1>
+class apply_visitor_binary_invoke_cpp14
+{
+    Visitor& visitor_;
+    Value1& value1_;
+
+public: // structors
+
+    apply_visitor_binary_invoke_cpp14(Visitor& visitor, Value1& value1) BOOST_NOEXCEPT
+        : visitor_(visitor)
+        , value1_(value1)
+    {
+    }
+
+public: // visitor interfaces
+
+    template <typename Value2>
+    decltype(auto) operator()(Value2& value2)
+    {
+        return visitor_(value1_, value2);
+    }
+
+private:
+    apply_visitor_binary_invoke_cpp14& operator=(const apply_visitor_binary_invoke_cpp14&);
+};
+
+template <typename Visitor, typename Visitable2>
+class apply_visitor_binary_unwrap_cpp14
+{
+    Visitor& visitor_;
+    Visitable2& visitable2_;
+
+public: // structors
+
+    apply_visitor_binary_unwrap_cpp14(Visitor& visitor, Visitable2& visitable2) BOOST_NOEXCEPT
+        : visitor_(visitor)
+        , visitable2_(visitable2)
+    {
+    }
+
+public: // visitor interfaces
+
+    template <typename Value1>
+    decltype(auto) operator()(Value1& value1)
+    {
+        apply_visitor_binary_invoke_cpp14<
+              Visitor
+            , Value1
+            > invoker(visitor_, value1);
+
+        return boost::apply_visitor(invoker, visitable2_);
+    }
+
+private:
+    apply_visitor_binary_unwrap_cpp14& operator=(const apply_visitor_binary_unwrap_cpp14&);
+};
+
+}} // namespace detail::variant
+
+template <typename Visitor, typename Visitable1, typename Visitable2>
+inline decltype(auto) apply_visitor(Visitor& visitor, Visitable1& visitable1, Visitable2& visitable2,
+    typename boost::disable_if<
+        boost::detail::variant::has_result_type<Visitor>
+    >::type* = 0)
+{
+    ::boost::detail::variant::apply_visitor_binary_unwrap_cpp14<
+          Visitor, Visitable2
+        > unwrapper(visitor, visitable2);
+
+    return boost::apply_visitor(unwrapper, visitable1);
+}
+
+template <typename Visitor, typename Visitable1, typename Visitable2>
+inline decltype(auto) apply_visitor(const Visitor& visitor, Visitable1& visitable1, Visitable2& visitable2,
+    typename boost::disable_if<
+        boost::detail::variant::has_result_type<Visitor>
+    >::type* = 0)
+{
+    ::boost::detail::variant::apply_visitor_binary_unwrap_cpp14<
+          const Visitor, Visitable2
+        > unwrapper(visitor, visitable2);
+
+    return boost::apply_visitor(unwrapper, visitable1);
+}
+
+#endif // !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+
 } // namespace boost
 
 #endif // BOOST_VARIANT_DETAIL_APPLY_VISITOR_BINARY_HPP

include/boost/variant/detail/apply_visitor_delayed.hpp

@@ -17,6 +17,11 @@
 
 #include "boost/variant/detail/apply_visitor_unary.hpp"
 #include "boost/variant/detail/apply_visitor_binary.hpp"
+#include "boost/variant/variant_fwd.hpp" // for BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+
+
+#include "boost/variant/detail/has_result_type.hpp"
+#include <boost/core/enable_if.hpp>
 
 namespace boost {
 
@@ -54,6 +59,18 @@ public: // structors
     {
     }
 
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+
+public: // N-ary visitor interface
+    template <typename... Visitables>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    operator()(Visitables&... visitables) const
+    {
+        return apply_visitor(visitor_, visitables...);
+    }
+
+#else // !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+
 public: // unary visitor interface
 
     template <typename Visitable>
@@ -72,17 +89,63 @@ public: // binary visitor interface
         return apply_visitor(visitor_, visitable1, visitable2);
     }
 
+#endif // !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+
 private:
     apply_visitor_delayed_t& operator=(const apply_visitor_delayed_t&);
 
 };
 
 template <typename Visitor>
-inline apply_visitor_delayed_t<Visitor> apply_visitor(Visitor& visitor)
+inline typename boost::enable_if<
+        boost::detail::variant::has_result_type<Visitor>,
+        apply_visitor_delayed_t<Visitor>
+    >::type apply_visitor(Visitor& visitor)
 {
     return apply_visitor_delayed_t<Visitor>(visitor);
 }
 
+#if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276) \
+    && !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+
+template <typename Visitor>
+class apply_visitor_delayed_cpp14_t
+{
+private: // representation
+    Visitor& visitor_;
+
+public: // structors
+
+    explicit apply_visitor_delayed_cpp14_t(Visitor& visitor) BOOST_NOEXCEPT
+      : visitor_(visitor)
+    {
+    }
+
+public: // N-ary visitor interface
+    template <typename... Visitables>
+    decltype(auto) operator()(Visitables&... visitables) const
+    {
+        return apply_visitor(visitor_, visitables...);
+    }
+
+private:
+    apply_visitor_delayed_cpp14_t& operator=(const apply_visitor_delayed_cpp14_t&);
+
+};
+
+template <typename Visitor>
+inline  typename boost::disable_if<
+        boost::detail::variant::has_result_type<Visitor>,
+        apply_visitor_delayed_cpp14_t<Visitor>
+    >::type apply_visitor(Visitor& visitor)
+{
+    return apply_visitor_delayed_cpp14_t<Visitor>(visitor);
+}
+
+#endif // !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+            // && !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+
+
 } // namespace boost
 
 #endif // BOOST_VARIANT_DETAIL_APPLY_VISITOR_DELAYED_HPP

include/boost/variant/detail/apply_visitor_unary.hpp

@@ -3,8 +3,8 @@
 // See http://www.boost.org for updates, documentation, and revision history.
 //-----------------------------------------------------------------------------
 //
-// Copyright (c) 2002-2003
-// Eric Friedman
+// Copyright (c) 2002-2003 Eric Friedman
+// Copyright (c) 2014 Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
@@ -18,11 +18,21 @@
 #include "boost/variant/detail/generic_result_type.hpp"
 
 #if BOOST_WORKAROUND(__EDG__, BOOST_TESTED_AT(302))
-#include "boost/utility/enable_if.hpp"
+#include "boost/core/enable_if.hpp"
 #include "boost/mpl/not.hpp"
 #include "boost/type_traits/is_const.hpp"
 #endif
 
+#if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+#   include <boost/mpl/distance.hpp>
+#   include <boost/mpl/advance.hpp>
+#   include <boost/mpl/deref.hpp>
+#   include <boost/mpl/size.hpp>
+#   include <boost/utility/declval.hpp>
+#   include <boost/core/enable_if.hpp>
+#   include "boost/variant/detail/has_result_type.hpp"
+#endif
+
 namespace boost {
 
 //////////////////////////////////////////////////////////////////////////
@@ -74,6 +84,90 @@ apply_visitor(const Visitor& visitor, Visitable& visitable)
     return visitable.apply_visitor(visitor);
 }
 
+
+#if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+
+// C++14
+namespace detail { namespace variant {
+
+// This class serves only metaprogramming purposes. none of its methods must be called at runtime!
+template <class Visitor, class Variant>
+struct result_multideduce1 {
+    typedef typename Variant::types                 types;
+    typedef typename boost::mpl::begin<types>::type begin_it;
+    typedef typename boost::mpl::advance<
+        begin_it, boost::mpl::int_<boost::mpl::size<types>::type::value - 1>
+    >::type                                         last_it;
+
+    // For metaprogramming purposes ONLY! Do not use this method (and class) at runtime!
+    static Visitor& vis() BOOST_NOEXCEPT {
+        // Functions that work with lambdas must be defined in same translation unit.
+        // Because of that, we can not use `boost::decval<Visitor&>()` here.
+        Visitor&(*f)() = 0; // pointer to function
+        return f();
+    }
+
+    static decltype(auto) deduce_impl(last_it, unsigned /*helper*/) {
+        typedef typename boost::mpl::deref<last_it>::type value_t;
+        return vis()( boost::declval< value_t& >() );
+    }
+
+    template <class It>
+    static decltype(auto) deduce_impl(It, unsigned helper) {
+        typedef typename boost::mpl::next<It>::type next_t;
+        typedef typename boost::mpl::deref<It>::type value_t;
+        if (helper == boost::mpl::distance<begin_it, It>::type::value) {
+            return deduce_impl(next_t(), ++helper);
+        }
+
+        return vis()( boost::declval< value_t& >() );
+    }
+
+    static decltype(auto) deduce() {
+        return deduce_impl(begin_it(), 0);
+    }
+};
+
+template <class Visitor, class Variant>
+struct result_wrapper1
+{
+    typedef decltype(result_multideduce1<Visitor, Variant>::deduce()) result_type;
+
+    Visitor& visitor_;
+    explicit result_wrapper1(Visitor& visitor) BOOST_NOEXCEPT
+        : visitor_(visitor)
+    {}
+
+    template <class T>
+    result_type operator()(T& val) const {
+        return visitor_(val);
+    }
+};
+
+}} // namespace detail::variant
+
+template <typename Visitor, typename Visitable>
+inline decltype(auto) apply_visitor(Visitor& visitor, Visitable& visitable,
+    typename boost::disable_if<
+        boost::detail::variant::has_result_type<Visitor>
+    >::type* = 0)
+{
+    boost::detail::variant::result_wrapper1<Visitor, Visitable> cpp14_vis(visitor);
+    return visitable.apply_visitor(cpp14_vis);
+}
+
+template <typename Visitor, typename Visitable>
+inline decltype(auto) apply_visitor(const Visitor& visitor, Visitable& visitable,
+    typename boost::disable_if<
+        boost::detail::variant::has_result_type<Visitor>
+    >::type* = 0)
+{
+    boost::detail::variant::result_wrapper1<const Visitor, Visitable> cpp14_vis(visitor);
+    return visitable.apply_visitor(cpp14_vis);
+}
+
+#endif // !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+
 } // namespace boost
 
 #endif // BOOST_VARIANT_DETAIL_APPLY_VISITOR_UNARY_HPP

include/boost/variant/detail/bool_trait_def.hpp

@@ -1,30 +0,0 @@
-//-----------------------------------------------------------------------------
-// boost/variant/detail/bool_trait_def.hpp header file
-// See http://www.boost.org for updates, documentation, and revision history.
-//-----------------------------------------------------------------------------
-//
-// Copyright (c) 2003
-// Eric Friedman
-//
-// 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)
-
-// Needed until move-related traits incorporated into type_traits library.
-// no include guards, the header is intended for multiple inclusion!
-
-// should be the last #include
-#include "boost/type_traits/detail/bool_trait_def.hpp"
-
-#define BOOST_VARIANT_TT_AUX_BOOL_TRAIT_DEF1(trait,T,C) \
-template< typename T > struct trait \
-    BOOST_TT_AUX_BOOL_C_BASE(C) \
-{ \
-    BOOST_TT_AUX_BOOL_TRAIT_VALUE_DECL(C) \
-    BOOST_MPL_AUX_LAMBDA_SUPPORT(1,trait,(T)) \
-}; \
-/**/
-
-#define BOOST_VARIANT_TT_AUX_TRAIT_SUFFIX(arity, name) \
-BOOST_TT_AUX_TEMPLATE_ARITY_SPEC(arity, name) \
-/**/

include/boost/variant/detail/bool_trait_undef.hpp

@@ -1,21 +0,0 @@
-//-----------------------------------------------------------------------------
-// boost/variant/detail/bool_trait_undef.hpp header file
-// See http://www.boost.org for updates, documentation, and revision history.
-//-----------------------------------------------------------------------------
-//
-// Copyright (c) 2003
-// Eric Friedman
-//
-// 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)
-
-// Needed until move-related traits incorporated into type_traits library.
-// no include guards, the header is intended for multiple inclusion!
-
-// should be the last #include
-#include "boost/type_traits/detail/bool_trait_undef.hpp"
-
-
-#undef BOOST_VARIANT_TT_AUX_BOOL_TRAIT_DEF1
-#undef BOOST_VARIANT_TT_AUX_TRAIT_SUFFIX

include/boost/variant/detail/element_index.hpp

@@ -0,0 +1,63 @@
+//-----------------------------------------------------------------------------
+// boost variant/detail/element_index.hpp header file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2014-2015 Antony Polukhin
+//
+// 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_VARIANT_DETAIL_ELEMENT_INDEX_HPP
+#define BOOST_VARIANT_DETAIL_ELEMENT_INDEX_HPP
+
+#include "boost/config.hpp"
+#include "boost/variant/recursive_wrapper_fwd.hpp"
+#include "boost/variant/variant_fwd.hpp"
+
+#include "boost/type_traits/remove_cv.hpp"
+#include "boost/type_traits/remove_reference.hpp"
+#include "boost/mpl/find_if.hpp"
+
+namespace boost { namespace detail { namespace variant {
+
+template <class VariantElement, class T>
+struct variant_element_functor :
+    boost::mpl::or_<
+        boost::is_same<VariantElement, T>,
+        boost::is_same<VariantElement, boost::recursive_wrapper<T> >,
+        boost::is_same<VariantElement, T& >
+    >
+{};
+
+template <class Types, class T>
+struct element_iterator_impl :
+    boost::mpl::find_if<
+        Types,
+        boost::mpl::or_<
+            variant_element_functor<boost::mpl::_1, T>,
+            variant_element_functor<boost::mpl::_1, typename boost::remove_cv<T>::type >
+        >
+    >
+{};
+
+template <class Variant, class T>
+struct element_iterator :
+    element_iterator_impl< typename Variant::types, typename boost::remove_reference<T>::type >
+{};
+
+template <class Variant, class T>
+struct holds_element :
+    boost::mpl::not_<
+        boost::is_same<
+            typename boost::mpl::end<typename Variant::types>::type,
+            typename element_iterator<Variant, T>::type
+        >
+    >
+{};
+
+
+}}} // namespace boost::detail::variant
+
+#endif // BOOST_VARIANT_DETAIL_ELEMENT_INDEX_HPP

include/boost/variant/detail/forced_return.hpp

@@ -17,10 +17,6 @@
 #include "boost/variant/detail/generic_result_type.hpp"
 #include "boost/assert.hpp"
 
-#if !defined(BOOST_MSVC)
-#   include "boost/type_traits/remove_reference.hpp"
-#endif
-
 namespace boost {
 namespace detail { namespace variant {
 
@@ -42,9 +38,8 @@ inline T forced_return()
     // logical error: should never be here! (see above)
     BOOST_ASSERT(false);
 
-    typedef typename boost::remove_reference<T>::type basic_type;
-    basic_type* dummy = 0;
-    return *static_cast< basic_type* >(dummy);
+    T (*dummy_function_ptr)() = 0;
+    return dummy_function_ptr();
 }
 
 template <>
@@ -76,6 +71,8 @@ forced_return()
 
 #else // defined(BOOST_MSVC)
 
+# pragma warning( push )
+# pragma warning( disable : 4702 ) // unreachable code
 // msvc-specific implementation
 //
 // Leverages __declspec(noreturn) for optimized implementation.
@@ -95,6 +92,8 @@ forced_return()
     forced_return_no_return();
 }
 
+# pragma warning( pop )
+
 #endif // BOOST_MSVC optimization
 
 }} // namespace detail::variant

include/boost/variant/detail/has_result_type.hpp

@@ -0,0 +1,37 @@
+//-----------------------------------------------------------------------------
+// boost variant/detail/has_result_type.hpp header file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2014-2015 Antony Polukhin
+//
+// 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_VARIANT_DETAIL_HAS_RESULT_TYPE_HPP
+#define BOOST_VARIANT_DETAIL_HAS_RESULT_TYPE_HPP
+
+#include "boost/config.hpp"
+#include "boost/type_traits/remove_reference.hpp"
+
+
+namespace boost { namespace detail { namespace variant {
+
+template <typename T >
+struct has_result_type {
+private:
+    typedef char                      yes;
+    typedef struct { char array[2]; } no;
+
+    template<typename C> static yes test(typename boost::remove_reference<typename C::result_type>::type*);
+    template<typename C> static no  test(...);
+
+public:
+    BOOST_STATIC_CONSTANT(bool, value = sizeof(test<T>(0)) == sizeof(yes));
+};
+
+}}} // namespace boost::detail::variant
+
+#endif // BOOST_VARIANT_DETAIL_HAS_RESULT_TYPE_HPP
+

include/boost/variant/detail/make_variant_list.hpp

@@ -32,7 +32,7 @@ namespace detail { namespace variant {
 // declaration workaround (below).
 //
 
-#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && defined(BOOST_VARIANT_USE_VARIADIC_TEMPLATES)
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
 
 template < typename... T >
 struct make_variant_list
@@ -40,7 +40,7 @@ struct make_variant_list
     typedef typename mpl::list< T... >::type type;
 };
 
-#else
+#else // defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
 
 template < BOOST_VARIANT_ENUM_PARAMS(typename T) >
 struct make_variant_list
@@ -65,7 +65,7 @@ public: // metafunction result
 
 };
 
-#endif // BOOST_NO_CXX11_VARIADIC_TEMPLATES
+#endif // BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES workaround
 
 }} // namespace detail::variant
 } // namespace boost

include/boost/variant/detail/move.hpp

@@ -5,7 +5,7 @@
 //
 //  Copyright (c) 2002-2003 Eric Friedman
 //  Copyright (c) 2002 by Andrei Alexandrescu
-//  Copyright (c) 2013 Antony Polukhin
+//  Copyright (c) 2013-2014 Antony Polukhin
 //
 //  Use, modification and distribution are subject to the
 //  Boost Software License, Version 1.0. (See accompanying file
@@ -26,6 +26,7 @@
 #include "boost/config.hpp"
 #include "boost/detail/workaround.hpp"
 #include "boost/move/move.hpp"
+#include "boost/move/adl_move_swap.hpp"
 
 namespace boost { namespace detail { namespace variant {
 
@@ -38,27 +39,10 @@ using boost::move;
 // types and on non-conforming compilers.
 //
 
-namespace move_swap_fallback {
-
-template <typename T1, typename T2>
-inline void swap(T1& lhs, T2& rhs)
-{
-    T1 tmp( boost::detail::variant::move(lhs) );
-    lhs = boost::detail::variant::move(rhs);
-    rhs = boost::detail::variant::move(tmp);
-}
-
-} // namespace move_swap_fallback
-
 template <typename T>
 inline void move_swap(T& lhs, T& rhs)
 {
-#if defined(BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP)
-    move_swap_fallback::swap(lhs, rhs);
-#else
-    using move_swap_fallback::swap;
-    swap(lhs, rhs);
-#endif
+    ::boost::adl_move_swap(lhs, rhs);
 }
 
 }}} // namespace boost::detail::variant

include/boost/variant/detail/multivisitors_cpp11_based.hpp

@@ -0,0 +1,183 @@
+//  Boost.Varaint
+//  Contains multivisitors that are implemented via variadic templates and std::tuple
+//
+//  See http://www.boost.org for most recent version, including documentation.
+//
+//  Copyright Antony Polukhin, 2013-2014.
+//
+//  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_VARIANT_DETAIL_MULTIVISITORS_CPP11_BASED_HPP
+#define BOOST_VARIANT_DETAIL_MULTIVISITORS_CPP11_BASED_HPP
+
+#if defined(_MSC_VER)
+# pragma once
+#endif
+
+#include <boost/variant/detail/apply_visitor_unary.hpp>
+#include "boost/variant/variant_fwd.hpp" // for BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+
+#if defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) || defined(BOOST_NO_CXX11_HDR_TUPLE)
+#   error "This file requires <tuple> and variadic templates support"
+#endif
+
+#include <tuple>
+
+namespace boost { 
+
+namespace detail { namespace variant {
+
+    // Implementing some of the C++14 features in C++11
+    template <std::size_t... I> class index_sequence {};
+
+    template <std::size_t N, std::size_t... I> 
+    struct make_index_sequence 
+        : make_index_sequence<N-1, N-1, I...> 
+    {};
+    template <std::size_t... I> 
+    struct make_index_sequence<0, I...> 
+        : index_sequence<I...> 
+    {};
+
+    template <class... Types>
+    std::tuple<Types&...> forward_as_tuple_simple(Types&... args) BOOST_NOEXCEPT
+    {
+        return std::tuple<Types&...>(args...);
+    }
+
+    // Implementing some of the helper tuple methods
+    template <std::size_t... I, typename Tuple>
+    std::tuple<typename std::tuple_element<I + 1, Tuple>::type...> 
+        tuple_tail_impl(const Tuple& tpl, index_sequence<I...>)
+    {
+        return std::tuple<
+            typename std::tuple_element<I + 1, Tuple>::type...
+        > (std::get<I + 1>(tpl)...);
+    }
+
+    template <typename Head, typename... Tail>
+    std::tuple<Tail...> tuple_tail(const std::tuple<Head, Tail...>& tpl)
+    {
+        return tuple_tail_impl(tpl, make_index_sequence<sizeof...(Tail)>());
+    }
+
+
+
+    // Forward declaration
+    template <typename Visitor, typename Visitables, typename... Values>
+    class one_by_one_visitor_and_value_referer;
+
+    template <typename Visitor, typename Visitables, typename... Values>
+    inline one_by_one_visitor_and_value_referer<Visitor, Visitables, Values... >
+        make_one_by_one_visitor_and_value_referer(
+            Visitor& visitor, Visitables visitables, std::tuple<Values&...> values
+        )
+    {
+        return one_by_one_visitor_and_value_referer<Visitor, Visitables, Values... > (
+            visitor, visitables, values
+        );
+    }
+
+    template <typename Visitor, typename Visitables, typename... Values>
+    class one_by_one_visitor_and_value_referer
+    {
+        Visitor&                        visitor_;
+        std::tuple<Values&...>          values_;
+        Visitables                      visitables_;
+
+    public: // structors
+        one_by_one_visitor_and_value_referer(
+                    Visitor& visitor, Visitables visitables, std::tuple<Values&...> values
+                ) BOOST_NOEXCEPT
+            : visitor_(visitor)
+            , values_(values)
+            , visitables_(visitables)
+        {}
+
+    public: // visitor interfaces
+        typedef typename Visitor::result_type result_type;
+
+        template <typename Value>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type) operator()(Value& value) const
+        {
+            return ::boost::apply_visitor(
+                make_one_by_one_visitor_and_value_referer(
+                    visitor_,
+                    tuple_tail(visitables_),
+                    std::tuple_cat(values_, std::tuple<Value&>(value))
+                )
+                , std::get<0>(visitables_) // getting Head element
+            );
+        }
+
+    private:
+        one_by_one_visitor_and_value_referer& operator=(const one_by_one_visitor_and_value_referer&);
+    };
+
+    template <typename Visitor, typename... Values>
+    class one_by_one_visitor_and_value_referer<Visitor, std::tuple<>, Values...>
+    {
+        Visitor&                        visitor_;
+        std::tuple<Values&...>          values_;
+
+    public:
+        one_by_one_visitor_and_value_referer(
+                    Visitor& visitor, std::tuple<> /*visitables*/, std::tuple<Values&...> values
+                ) BOOST_NOEXCEPT
+            : visitor_(visitor)
+            , values_(values)
+        {}
+
+        typedef typename Visitor::result_type result_type;
+
+        template <class Tuple, std::size_t... I>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type) do_call(Tuple t, index_sequence<I...>) const {
+            return visitor_(std::get<I>(t)...);
+        }
+
+        template <typename Value>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type) operator()(Value& value) const
+        {
+            return do_call(
+                std::tuple_cat(values_, std::tuple<Value&>(value)),
+                make_index_sequence<sizeof...(Values) + 1>()
+            );
+        }
+    };
+
+}} // namespace detail::variant
+
+    template <class Visitor, class T1, class T2, class T3, class... TN>
+    inline BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(typename Visitor::result_type)
+        apply_visitor(const Visitor& visitor, T1& v1, T2& v2, T3& v3, TN&... vn)
+    {
+        return ::boost::apply_visitor(
+            ::boost::detail::variant::make_one_by_one_visitor_and_value_referer(
+                visitor,
+                ::boost::detail::variant::forward_as_tuple_simple(v2, v3, vn...),
+                std::tuple<>()
+            ),
+            v1
+        );
+    }
+    
+    template <class Visitor, class T1, class T2, class T3, class... TN>
+    inline BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(typename Visitor::result_type)
+        apply_visitor(Visitor& visitor, T1& v1, T2& v2, T3& v3, TN&... vn)
+    {
+        return ::boost::apply_visitor(
+            ::boost::detail::variant::make_one_by_one_visitor_and_value_referer(
+                visitor,
+                ::boost::detail::variant::forward_as_tuple_simple(v2, v3, vn...),
+                std::tuple<>()
+            ),
+            v1
+        );
+    }
+
+} // namespace boost
+
+#endif // BOOST_VARIANT_DETAIL_MULTIVISITORS_CPP11_BASED_HPP
+

include/boost/variant/detail/multivisitors_cpp14_based.hpp

@@ -0,0 +1,142 @@
+//  Boost.Varaint
+//  Contains multivisitors that are implemented via variadic templates, std::tuple
+//  and decltype(auto)
+//
+//  See http://www.boost.org for most recent version, including documentation.
+//
+//  Copyright Antony Polukhin, 2013-2014.
+//
+//  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_VARIANT_DETAIL_MULTIVISITORS_CPP14_BASED_HPP
+#define BOOST_VARIANT_DETAIL_MULTIVISITORS_CPP14_BASED_HPP
+
+#if defined(_MSC_VER)
+# pragma once
+#endif
+
+#include <boost/variant/detail/multivisitors_cpp14_based.hpp>
+
+namespace boost { 
+
+namespace detail { namespace variant {
+
+    // Forward declaration
+    template <typename Visitor, typename Visitables, typename... Values>
+    class one_by_one_visitor_and_value_referer_cpp14;
+
+    template <typename Visitor, typename Visitables, typename... Values>
+    inline one_by_one_visitor_and_value_referer_cpp14<Visitor, Visitables, Values... >
+        make_one_by_one_visitor_and_value_referer_cpp14(
+            Visitor& visitor, Visitables visitables, std::tuple<Values&...> values
+        )
+    {
+        return one_by_one_visitor_and_value_referer_cpp14<Visitor, Visitables, Values... > (
+            visitor, visitables, values
+        );
+    }
+
+    template <typename Visitor, typename Visitables, typename... Values>
+    class one_by_one_visitor_and_value_referer_cpp14
+    {
+        Visitor&                        visitor_;
+        std::tuple<Values&...>          values_;
+        Visitables                      visitables_;
+
+    public: // structors
+        one_by_one_visitor_and_value_referer_cpp14(
+                    Visitor& visitor, Visitables visitables, std::tuple<Values&...> values
+                ) BOOST_NOEXCEPT
+            : visitor_(visitor)
+            , values_(values)
+            , visitables_(visitables)
+        {}
+
+    public: // visitor interfaces
+        template <typename Value>
+        decltype(auto) operator()(Value& value) const
+        {
+            return ::boost::apply_visitor(
+                make_one_by_one_visitor_and_value_referer_cpp14(
+                    visitor_,
+                    tuple_tail(visitables_),
+                    std::tuple_cat(values_, std::tuple<Value&>(value))
+                )
+                , std::get<0>(visitables_) // getting Head element
+            );
+        }
+
+    private:
+        one_by_one_visitor_and_value_referer_cpp14& operator=(const one_by_one_visitor_and_value_referer_cpp14&);
+    };
+
+    template <typename Visitor, typename... Values>
+    class one_by_one_visitor_and_value_referer_cpp14<Visitor, std::tuple<>, Values...>
+    {
+        Visitor&                        visitor_;
+        std::tuple<Values&...>          values_;
+
+    public:
+        one_by_one_visitor_and_value_referer_cpp14(
+                    Visitor& visitor, std::tuple<> /*visitables*/, std::tuple<Values&...> values
+                ) BOOST_NOEXCEPT
+            : visitor_(visitor)
+            , values_(values)
+        {}
+
+        template <class Tuple, std::size_t... I>
+        decltype(auto) do_call(Tuple t, index_sequence<I...>) const {
+            return visitor_(std::get<I>(t)...);
+        }
+
+        template <typename Value>
+        decltype(auto) operator()(Value& value) const
+        {
+            return do_call(
+                std::tuple_cat(values_, std::tuple<Value&>(value)),
+                make_index_sequence<sizeof...(Values) + 1>()
+            );
+        }
+    };
+
+}} // namespace detail::variant
+
+    template <class Visitor, class T1, class T2, class T3, class... TN>
+    inline decltype(auto) apply_visitor(const Visitor& visitor, T1& v1, T2& v2, T3& v3, TN&... vn,
+        typename boost::disable_if<
+            boost::detail::variant::has_result_type<Visitor>
+        >::type* = 0)
+    {
+        return boost::apply_visitor(
+            ::boost::detail::variant::make_one_by_one_visitor_and_value_referer_cpp14(
+                visitor,
+                ::boost::detail::variant::forward_as_tuple_simple(v2, v3, vn...),
+                std::tuple<>()
+            ),
+            v1
+        );
+    }
+    
+
+    template <class Visitor, class T1, class T2, class T3, class... TN>
+    inline decltype(auto) apply_visitor(Visitor& visitor, T1& v1, T2& v2, T3& v3, TN&... vn,
+        typename boost::disable_if<
+            boost::detail::variant::has_result_type<Visitor>
+        >::type* = 0)
+    {
+        return ::boost::apply_visitor(
+            ::boost::detail::variant::make_one_by_one_visitor_and_value_referer_cpp14(
+                visitor,
+                ::boost::detail::variant::forward_as_tuple_simple(v2, v3, vn...),
+                std::tuple<>()
+            ),
+            v1
+        );
+    }
+
+} // namespace boost
+
+#endif // BOOST_VARIANT_DETAIL_MULTIVISITORS_CPP14_BASED_HPP
+

include/boost/variant/detail/multivisitors_preprocessor_based.hpp

@@ -0,0 +1,143 @@
+//  Boost.Varaint
+//  Contains multivisitors that are implemented via preprocessor magic
+//
+//  See http://www.boost.org for most recent version, including documentation.
+//
+//  Copyright Antony Polukhin, 2013-2014.
+//
+//  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_VARIANT_DETAIL_MULTIVISITORS_PREPROCESSOR_BASED_HPP
+#define BOOST_VARIANT_DETAIL_MULTIVISITORS_PREPROCESSOR_BASED_HPP
+
+#if defined(_MSC_VER)
+# pragma once
+#endif
+
+#include <boost/variant.hpp>
+#include <boost/bind.hpp>
+
+#include <boost/preprocessor/repetition.hpp>
+#include <boost/preprocessor/punctuation/comma_if.hpp>
+#include <boost/preprocessor/arithmetic/add.hpp>
+#include <boost/preprocessor/arithmetic/sub.hpp>
+
+#ifndef BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS
+#   define BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS 4
+#endif
+
+namespace boost { 
+
+namespace detail { namespace variant {
+
+    template <class VisitorT, class Visitable1T, class Visitable2T>
+    struct two_variables_holder {
+    private:
+        VisitorT&       visitor_;
+        Visitable1T&    visitable1_;
+        Visitable2T&    visitable2_;
+
+        // required to suppress warnings and ensure that we do not copy
+        // this visitor
+        two_variables_holder& operator=(const two_variables_holder&);
+
+    public:
+        typedef BOOST_DEDUCED_TYPENAME VisitorT::result_type result_type;
+
+        explicit two_variables_holder(VisitorT& visitor, Visitable1T& visitable1, Visitable2T& visitable2) BOOST_NOEXCEPT 
+            : visitor_(visitor)
+            , visitable1_(visitable1)
+            , visitable2_(visitable2)
+        {}
+
+#define BOOST_VARIANT_OPERATOR_BEG()                            \
+    return ::boost::apply_visitor(                              \
+    ::boost::bind<result_type>(boost::ref(visitor_), _1, _2     \
+    /**/
+
+#define BOOST_VARIANT_OPERATOR_END()                            \
+    ), visitable1_, visitable2_);                               \
+    /**/
+
+#define BOOST_VARANT_VISITORS_VARIABLES_PRINTER(z, n, data)     \
+    BOOST_PP_COMMA() boost::ref( BOOST_PP_CAT(vis, n) )         \
+    /**/
+
+#define BOOST_VARIANT_VISIT(z, n, data)                                                     \
+    template <BOOST_PP_ENUM_PARAMS(BOOST_PP_ADD(n, 1), class VisitableUnwrapped)>           \
+    BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type) operator()(                          \
+        BOOST_PP_ENUM_BINARY_PARAMS(BOOST_PP_ADD(n, 1), VisitableUnwrapped, & vis)          \
+    ) const                                                                                 \
+    {                                                                                       \
+        BOOST_VARIANT_OPERATOR_BEG()                                                        \
+        BOOST_PP_REPEAT(BOOST_PP_ADD(n, 1), BOOST_VARANT_VISITORS_VARIABLES_PRINTER, ~)     \
+        BOOST_VARIANT_OPERATOR_END()                                                        \
+    }                                                                                       \
+    /**/
+
+BOOST_PP_REPEAT( BOOST_PP_SUB(BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS, 2), BOOST_VARIANT_VISIT, ~)
+#undef BOOST_VARIANT_OPERATOR_BEG
+#undef BOOST_VARIANT_OPERATOR_END
+#undef BOOST_VARANT_VISITORS_VARIABLES_PRINTER
+#undef BOOST_VARIANT_VISIT
+
+    };
+
+    template <class VisitorT, class Visitable1T, class Visitable2T>
+    inline two_variables_holder<VisitorT, Visitable1T, Visitable2T> make_two_variables_holder(
+            VisitorT& visitor, Visitable1T& visitable1, Visitable2T& visitable2
+        ) BOOST_NOEXCEPT
+    {
+        return two_variables_holder<VisitorT, Visitable1T, Visitable2T>(visitor, visitable1, visitable2);
+    }
+
+    template <class VisitorT, class Visitable1T, class Visitable2T>
+    inline two_variables_holder<const VisitorT, Visitable1T, Visitable2T> make_two_variables_holder(
+            const VisitorT& visitor, Visitable1T& visitable1, Visitable2T& visitable2
+        ) BOOST_NOEXCEPT
+    {
+        return two_variables_holder<const VisitorT, Visitable1T, Visitable2T>(visitor, visitable1, visitable2);
+    }
+
+}} // namespace detail::variant
+
+#define BOOST_VARIANT_APPLY_VISITOR_BEG()                                               \
+    return ::boost::apply_visitor(                                                      \
+            boost::detail::variant::make_two_variables_holder(visitor, var0 , var1),    \
+            var2                                                                        \
+    /**/
+
+#define BOOST_VARIANT_APPLY_VISITOR_END()                       \
+    );                                                          \
+    /**/
+
+#define BOOST_VARANT_VISITORS_VARIABLES_PRINTER(z, n, data)     \
+    BOOST_PP_COMMA() BOOST_PP_CAT(var, BOOST_PP_ADD(n, 3))      \
+    /**/
+
+#define BOOST_VARIANT_VISIT(z, n, data)                                                                 \
+    template <class Visitor BOOST_PP_COMMA() BOOST_PP_ENUM_PARAMS(BOOST_PP_ADD(n, 3), class T)>         \
+    inline BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(BOOST_DEDUCED_TYPENAME Visitor::result_type) apply_visitor( \
+        data BOOST_PP_COMMA() BOOST_PP_ENUM_BINARY_PARAMS(BOOST_PP_ADD(n, 3), T, & var)     \
+    )                                                                                                   \
+    {                                                                                                   \
+        BOOST_VARIANT_APPLY_VISITOR_BEG()                                                               \
+        BOOST_PP_REPEAT(n, BOOST_VARANT_VISITORS_VARIABLES_PRINTER, ~)                                  \
+        BOOST_VARIANT_APPLY_VISITOR_END()                                                               \
+    }                                                                                                   \
+    /**/
+
+BOOST_PP_REPEAT( BOOST_PP_SUB(BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS, 2), BOOST_VARIANT_VISIT, const Visitor& visitor)
+BOOST_PP_REPEAT( BOOST_PP_SUB(BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS, 2), BOOST_VARIANT_VISIT, Visitor& visitor)
+
+#undef BOOST_VARIANT_APPLY_VISITOR_BEG
+#undef BOOST_VARIANT_APPLY_VISITOR_END
+#undef BOOST_VARANT_VISITORS_VARIABLES_PRINTER
+#undef BOOST_VARIANT_VISIT
+    
+} // namespace boost
+
+#endif // BOOST_VARIANT_DETAIL_MULTIVISITORS_PREPROCESSOR_BASED_HPP
+

include/boost/variant/detail/substitute.hpp

@@ -21,6 +21,7 @@
 #include "boost/mpl/aux_/config/ctps.hpp"
 
 #include "boost/variant/detail/substitute_fwd.hpp"
+#include "boost/variant/variant_fwd.hpp" // for BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
 #include "boost/mpl/aux_/lambda_arity_param.hpp"
 #include "boost/mpl/aux_/preprocessor/params.hpp"
 #include "boost/mpl/aux_/preprocessor/repeat.hpp"
@@ -125,6 +126,27 @@ struct substitute<
 // template expression (i.e., F<...>) specializations
 //
 
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+template <
+      template <typename...> class F
+    , typename... Ts
+    , typename Dest
+    , typename Source
+      BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(typename Arity)
+    >
+struct substitute<
+      F<Ts...>
+    , Dest
+    , Source
+      BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(Arity)
+    >
+{
+    typedef F<typename substitute<
+          Ts, Dest, Source
+        >::type...> type;
+};
+#endif // !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+
 #define BOOST_VARIANT_AUX_SUBSTITUTE_TYPEDEF_IMPL(N) \
     typedef typename substitute< \
           BOOST_PP_CAT(U,N), Dest, Source \

include/boost/variant/detail/visitation_impl.hpp

@@ -19,8 +19,8 @@
 #include "boost/variant/detail/cast_storage.hpp"
 #include "boost/variant/detail/forced_return.hpp"
 #include "boost/variant/detail/generic_result_type.hpp"
+#include "boost/variant/variant_fwd.hpp" // for BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
 
-#include "boost/assert.hpp"
 #include "boost/mpl/eval_if.hpp"
 #include "boost/mpl/bool.hpp"
 #include "boost/mpl/identity.hpp"
@@ -47,10 +47,18 @@
 // and potentially increase runtime performance. (TODO: Investigate further.)
 //
 #if !defined(BOOST_VARIANT_VISITATION_UNROLLING_LIMIT)
+
+#ifndef BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+#   include "boost/mpl/limits/list.hpp"
+#   define BOOST_VARIANT_VISITATION_UNROLLING_LIMIT   \
+        BOOST_MPL_LIMIT_LIST_SIZE
+#else
 #   define BOOST_VARIANT_VISITATION_UNROLLING_LIMIT   \
         BOOST_VARIANT_LIMIT_TYPES
 #endif
 
+#endif
+
 namespace boost {
 namespace detail { namespace variant {
 
@@ -154,8 +162,7 @@ inline
     BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(typename Visitor::result_type)
 visitation_impl_invoke(int, Visitor&, VoidPtrCV, apply_visitor_unrolled*, NBF, long)
 {
-    // should never be here at runtime:
-    BOOST_ASSERT(false);
+    // should never be here at runtime!
     typedef typename Visitor::result_type result_type;
     return ::boost::detail::variant::forced_return< result_type >();
 }
@@ -179,8 +186,7 @@ visitation_impl(
     , NBF, W* = 0, S* = 0
     )
 {
-    // should never be here at runtime:
-    BOOST_ASSERT(false);
+    // should never be here at runtime!
     typedef typename Visitor::result_type result_type;
     return ::boost::detail::variant::forced_return< result_type >();
 }

include/boost/variant/get.hpp

@@ -3,8 +3,8 @@
 // See http://www.boost.org for updates, documentation, and revision history.
 //-----------------------------------------------------------------------------
 //
-// Copyright (c) 2003
-// Eric Friedman, Itay Maman
+// Copyright (c) 2003 Eric Friedman, Itay Maman
+// Copyright (c) 2014 Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
@@ -17,9 +17,11 @@
 
 #include "boost/config.hpp"
 #include "boost/detail/workaround.hpp"
+#include "boost/static_assert.hpp"
 #include "boost/throw_exception.hpp"
 #include "boost/utility/addressof.hpp"
 #include "boost/variant/variant_fwd.hpp"
+#include "boost/variant/detail/element_index.hpp"
 
 #include "boost/type_traits/add_reference.hpp"
 #include "boost/type_traits/add_pointer.hpp"
@@ -31,7 +33,7 @@ namespace boost {
 //
 // The exception thrown in the event of a failed get of a value.
 //
-class bad_get
+class BOOST_SYMBOL_VISIBLE bad_get
     : public std::exception
 {
 public: // std::exception implementation
@@ -86,17 +88,22 @@ public: // visitor interfaces
 
 }} // namespace detail::variant
 
-#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0551))
-#   define BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(t)
-#else
-#   define BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(t)  \
-    , t* = 0
+#ifndef BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE
+#   if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0551))
+#       define BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(t)
+#   else
+#       define BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(t)  \
+        , t* = 0
+#   endif
 #endif
 
+/////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// relaxed_get<U>(variant) methods
+//
 template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
 inline
     typename add_pointer<U>::type
-get(
+relaxed_get(
       boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
       BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
     ) BOOST_NOEXCEPT
@@ -111,7 +118,7 @@ get(
 template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
 inline
     typename add_pointer<const U>::type
-get(
+relaxed_get(
       const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
       BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
     ) BOOST_NOEXCEPT
@@ -126,19 +133,158 @@ get(
 template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
 inline
     typename add_reference<U>::type
-get(
+relaxed_get(
       boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
       BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
     )
 {
     typedef typename add_pointer<U>::type U_ptr;
-    U_ptr result = get<U>(&operand);
+    U_ptr result = relaxed_get<U>(&operand);
 
     if (!result)
         boost::throw_exception(bad_get());
     return *result;
 }
 
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<const U>::type
+relaxed_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+    typedef typename add_pointer<const U>::type U_ptr;
+    U_ptr result = relaxed_get<const U>(&operand);
+
+    if (!result)
+        boost::throw_exception(bad_get());
+    return *result;
+}
+
+
+
+/////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// strict_get<U>(variant) methods
+//
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<U>::type
+strict_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::get<U>(boost::variant<T...>*) will always return NULL"
+    );
+
+    return relaxed_get<U>(operand);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<const U>::type
+strict_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, const U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::get<U>(const boost::variant<T...>*) will always return NULL"
+    );
+
+    return relaxed_get<U>(operand);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<U>::type
+strict_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::get<U>(boost::variant<T...>&) will always throw boost::bad_get exception"
+    );
+
+    return relaxed_get<U>(operand);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<const U>::type
+strict_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, const U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::get<U>(const boost::variant<T...>&) will always throw boost::bad_get exception"
+    );
+
+    return relaxed_get<U>(operand);
+}
+
+/////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// get<U>(variant) methods
+//
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<U>::type
+get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return relaxed_get<U>(operand);
+#else
+    return strict_get<U>(operand);
+#endif
+
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<const U>::type
+get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return relaxed_get<U>(operand);
+#else
+    return strict_get<U>(operand);
+#endif
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<U>::type
+get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return relaxed_get<U>(operand);
+#else
+    return strict_get<U>(operand);
+#endif
+}
+
 template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
 inline
     typename add_reference<const U>::type
@@ -147,12 +293,11 @@ get(
       BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
     )
 {
-    typedef typename add_pointer<const U>::type U_ptr;
-    U_ptr result = get<const U>(&operand);
-
-    if (!result)
-        boost::throw_exception(bad_get());
-    return *result;
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return relaxed_get<U>(operand);
+#else
+    return strict_get<U>(operand);
+#endif
 }
 
 } // namespace boost

include/boost/variant/multivisitors.hpp

@@ -3,7 +3,7 @@
 //
 //  See http://www.boost.org for most recent version, including documentation.
 //
-//  Copyright Antony Polukhin, 2013.
+//  Copyright Antony Polukhin, 2013-2014.
 //
 //  Distributed under the Boost
 //  Software License, Version 1.0. (See accompanying file
@@ -16,128 +16,17 @@
 # pragma once
 #endif
 
-#include <boost/variant.hpp>
-#include <boost/bind.hpp>
+#include <boost/config.hpp>
+#include "boost/variant/variant_fwd.hpp" // for BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
 
-#include <boost/preprocessor/repetition.hpp>
-#include <boost/preprocessor/punctuation/comma_if.hpp>
-#include <boost/preprocessor/arithmetic/add.hpp>
-#include <boost/preprocessor/arithmetic/sub.hpp>
-
-#ifndef BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS
-#   define BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS 4
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
+#   include <boost/variant/detail/multivisitors_cpp11_based.hpp>
+#   if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
+#       include <boost/variant/detail/multivisitors_cpp14_based.hpp>
+#   endif
+#else
+#   include <boost/variant/detail/multivisitors_preprocessor_based.hpp>
 #endif
 
-namespace boost { 
-
-namespace detail { namespace variant {
-
-    template <class VisitorT, class Visitable1T, class Visitable2T>
-    struct two_variables_holder {
-    private:
-        VisitorT&       visitor_;
-        Visitable1T&    visitable1_;
-        Visitable2T&    visitable2_;
-
-        // required to supress warnings and enshure that we do not copy 
-        // this visitor
-        two_variables_holder& operator=(const two_variables_holder&);
-
-    public:
-        typedef BOOST_DEDUCED_TYPENAME VisitorT::result_type result_type;
-
-        explicit two_variables_holder(VisitorT& visitor, Visitable1T& visitable1, Visitable2T& visitable2) BOOST_NOEXCEPT 
-            : visitor_(visitor)
-            , visitable1_(visitable1)
-            , visitable2_(visitable2)
-        {}
-
-#define BOOST_VARIANT_OPERATOR_BEG()                            \
-    return ::boost::apply_visitor(                              \
-    ::boost::bind<result_type>(boost::ref(visitor_), _1, _2     \
-    /**/
-
-#define BOOST_VARIANT_OPERATOR_END()                            \
-    ), visitable1_, visitable2_);                               \
-    /**/
-
-#define BOOST_VARANT_VISITORS_VARIABLES_PRINTER(z, n, data)     \
-    BOOST_PP_COMMA() boost::ref( BOOST_PP_CAT(vis, n) )         \
-    /**/
-
-#define BOOST_VARIANT_VISIT(z, n, data)                                                     \
-    template <BOOST_PP_ENUM_PARAMS(BOOST_PP_ADD(n, 1), class VisitableUnwrapped)>           \
-    BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type) operator()(                          \
-        BOOST_PP_ENUM_BINARY_PARAMS(BOOST_PP_ADD(n, 1), VisitableUnwrapped, & vis)          \
-    ) const                                                                                 \
-    {                                                                                       \
-        BOOST_VARIANT_OPERATOR_BEG()                                                        \
-        BOOST_PP_REPEAT(BOOST_PP_ADD(n, 1), BOOST_VARANT_VISITORS_VARIABLES_PRINTER, ~)     \
-        BOOST_VARIANT_OPERATOR_END()                                                        \
-    }                                                                                       \
-    /**/
-
-BOOST_PP_REPEAT( BOOST_PP_SUB(BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS, 2), BOOST_VARIANT_VISIT, ~)
-#undef BOOST_VARIANT_OPERATOR_BEG
-#undef BOOST_VARIANT_OPERATOR_END
-#undef BOOST_VARANT_VISITORS_VARIABLES_PRINTER
-#undef BOOST_VARIANT_VISIT
-
-    };
-
-    template <class VisitorT, class Visitable1T, class Visitable2T>
-    inline two_variables_holder<VisitorT, Visitable1T, Visitable2T> make_two_variables_holder(
-            VisitorT& visitor, Visitable1T& visitable1, Visitable2T& visitable2
-        ) BOOST_NOEXCEPT
-    {
-        return two_variables_holder<VisitorT, Visitable1T, Visitable2T>(visitor, visitable1, visitable2);
-    }
-
-    template <class VisitorT, class Visitable1T, class Visitable2T>
-    inline two_variables_holder<const VisitorT, Visitable1T, Visitable2T> make_two_variables_holder(
-            const VisitorT& visitor, Visitable1T& visitable1, Visitable2T& visitable2
-        ) BOOST_NOEXCEPT
-    {
-        return two_variables_holder<const VisitorT, Visitable1T, Visitable2T>(visitor, visitable1, visitable2);
-    }
-
-}} // namespace detail::variant
-
-#define BOOST_VARIANT_APPLY_VISITOR_BEG()                                               \
-    return ::boost::apply_visitor(                                                      \
-            boost::detail::variant::make_two_variables_holder(visitor, var0 , var1),    \
-            var2                                                                        \
-    /**/
-
-#define BOOST_VARIANT_APPLY_VISITOR_END()                       \
-    );                                                          \
-    /**/
-
-#define BOOST_VARANT_VISITORS_VARIABLES_PRINTER(z, n, data)     \
-    BOOST_PP_COMMA() BOOST_PP_CAT(var, BOOST_PP_ADD(n, 3))      \
-    /**/
-
-#define BOOST_VARIANT_VISIT(z, n, data)                                                                 \
-    template <class Visitor BOOST_PP_COMMA() BOOST_PP_ENUM_PARAMS(BOOST_PP_ADD(n, 3), class T)>         \
-    inline BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(BOOST_DEDUCED_TYPENAME Visitor::result_type) apply_visitor( \
-        data BOOST_PP_COMMA() BOOST_PP_ENUM_BINARY_PARAMS(BOOST_PP_ADD(n, 3), T, & var)     \
-    )                                                                                                   \
-    {                                                                                                   \
-        BOOST_VARIANT_APPLY_VISITOR_BEG()                                                               \
-        BOOST_PP_REPEAT(n, BOOST_VARANT_VISITORS_VARIABLES_PRINTER, ~)                                  \
-        BOOST_VARIANT_APPLY_VISITOR_END()                                                               \
-    }                                                                                                   \
-    /**/
-
-BOOST_PP_REPEAT( BOOST_PP_SUB(BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS, 2), BOOST_VARIANT_VISIT, const Visitor& visitor)
-BOOST_PP_REPEAT( BOOST_PP_SUB(BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS, 2), BOOST_VARIANT_VISIT, Visitor& visitor)
-
-#undef BOOST_VARIANT_APPLY_VISITOR_BEG
-#undef BOOST_VARIANT_APPLY_VISITOR_END
-#undef BOOST_VARANT_VISITORS_VARIABLES_PRINTER
-#undef BOOST_VARIANT_VISIT
-    
-} // namespace boost
-
 #endif // BOOST_VARIANT_MULTIVISITORS_HPP
 

include/boost/variant/polymorphic_get.hpp

@@ -0,0 +1,344 @@
+//-----------------------------------------------------------------------------
+// boost variant/polymorphic_get.hpp header file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2013-2015 Antony Polukhin
+//
+// 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_VARIANT_POLYMORPHIC_GET_HPP
+#define BOOST_VARIANT_POLYMORPHIC_GET_HPP
+
+#include <exception>
+
+#include "boost/config.hpp"
+#include "boost/detail/workaround.hpp"
+#include "boost/static_assert.hpp"
+#include "boost/throw_exception.hpp"
+#include "boost/utility/addressof.hpp"
+#include "boost/variant/variant_fwd.hpp"
+#include "boost/variant/get.hpp"
+
+#include "boost/type_traits/add_reference.hpp"
+#include "boost/type_traits/add_pointer.hpp"
+#include "boost/type_traits/is_base_of.hpp"
+
+namespace boost {
+
+//////////////////////////////////////////////////////////////////////////
+// class bad_polymorphic_get
+//
+// The exception thrown in the event of a failed get of a value.
+//
+class BOOST_SYMBOL_VISIBLE bad_polymorphic_get
+    : public bad_get
+{
+public: // std::exception implementation
+
+    virtual const char * what() const BOOST_NOEXCEPT_OR_NOTHROW
+    {
+        return "boost::bad_polymorphic_get: "
+               "failed value get using boost::polymorphic_get";
+    }
+
+};
+
+//////////////////////////////////////////////////////////////////////////
+// function template get<T>
+//
+// Retrieves content of given variant object if content is of type T.
+// Otherwise: pointer ver. returns 0; reference ver. throws bad_get.
+//
+
+namespace detail { namespace variant {
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+// polymorphic metafunctions to detect index of a value
+//
+
+template <class Types, class T>
+struct element_polymorphic_iterator_impl :
+    boost::mpl::find_if<
+        Types,
+        boost::mpl::or_<
+            variant_element_functor<boost::mpl::_1, T>,
+            variant_element_functor<boost::mpl::_1, typename boost::remove_cv<T>::type >,
+            boost::is_base_of<T, boost::mpl::_1>
+        >
+    >
+{};
+
+template <class Variant, class T>
+struct holds_element_polymorphic :
+    boost::mpl::not_<
+        boost::is_same<
+            typename boost::mpl::end<typename Variant::types>::type,
+            typename element_polymorphic_iterator_impl<typename Variant::types, typename boost::remove_reference<T>::type >::type
+        >
+    >
+{};
+
+// (detail) class template get_polymorphic_visitor
+//
+// Generic static visitor that: if the value is of the specified
+// type or of a type derived from specified, returns a pointer
+// to the value it visits; else a null pointer.
+//
+template <typename Base>
+struct get_polymorphic_visitor
+{
+private: // private typedefs
+    typedef get_polymorphic_visitor<Base>       this_type;
+    typedef typename add_pointer<Base>::type    pointer;
+    typedef typename add_reference<Base>::type  reference;
+
+    pointer get(reference operand, boost::true_type) const BOOST_NOEXCEPT
+    {
+        return boost::addressof(operand);
+    }
+
+    template <class T>
+    pointer get(T&, boost::false_type) const BOOST_NOEXCEPT
+    {
+        return static_cast<pointer>(0);
+    }
+
+public: // visitor interfaces
+    typedef pointer result_type;
+
+    template <typename U>
+    pointer operator()(U& operand) const BOOST_NOEXCEPT
+    {
+        typedef boost::integral_constant<
+            bool,
+            boost::mpl::or_<
+                boost::is_base_of<Base, U>,
+                boost::is_same<Base, U>,
+                boost::is_same<typename boost::remove_cv<Base>::type, U >
+            >::value
+        > tag_t;
+
+        return this_type::get(operand, tag_t());
+    }
+};
+
+}} // namespace detail::variant
+
+#ifndef BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE
+#   if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0551))
+#       define BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(t)
+#   else
+#       define BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(t)  \
+        , t* = 0
+#   endif
+#endif
+
+//////////////////////////////////////////////////////////////////////////////////////////////////////////
+// polymorphic_relaxed_get
+//
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<U>::type
+polymorphic_relaxed_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+    typedef typename add_pointer<U>::type U_ptr;
+    if (!operand) return static_cast<U_ptr>(0);
+
+    detail::variant::get_polymorphic_visitor<U> v;
+    return operand->apply_visitor(v);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<const U>::type
+polymorphic_relaxed_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+    typedef typename add_pointer<const U>::type U_ptr;
+    if (!operand) return static_cast<U_ptr>(0);
+
+    detail::variant::get_polymorphic_visitor<const U> v;
+    return operand->apply_visitor(v);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<U>::type
+polymorphic_relaxed_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+    typedef typename add_pointer<U>::type U_ptr;
+    U_ptr result = polymorphic_relaxed_get<U>(&operand);
+
+    if (!result)
+        boost::throw_exception(bad_polymorphic_get());
+    return *result;
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<const U>::type
+polymorphic_relaxed_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+    typedef typename add_pointer<const U>::type U_ptr;
+    U_ptr result = polymorphic_relaxed_get<const U>(&operand);
+
+    if (!result)
+        boost::throw_exception(bad_polymorphic_get());
+    return *result;
+}
+
+//////////////////////////////////////////////////////////////////////////////////////////////////////////
+// polymorphic_strict_get
+//
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<U>::type
+polymorphic_strict_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element_polymorphic<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::polymorphic_get<U>(boost::variant<T...>*) will always return NULL"
+    );
+
+    return polymorphic_relaxed_get<U>(operand);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<const U>::type
+polymorphic_strict_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element_polymorphic<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::polymorphic_get<U>(const boost::variant<T...>*) will always return NULL"
+    );
+
+    return polymorphic_relaxed_get<U>(operand);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<U>::type
+polymorphic_strict_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element_polymorphic<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::polymorphic_get<U>(boost::variant<T...>&) will always throw boost::bad_polymorphic_get exception"
+    );
+
+    return polymorphic_relaxed_get<U>(operand);
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<const U>::type
+polymorphic_strict_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+    BOOST_STATIC_ASSERT_MSG(
+        (boost::detail::variant::holds_element_polymorphic<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value),
+        "boost::variant does not contain specified type U, "
+        "call to boost::polymorphic_get<U>(const boost::variant<T...>&) will always throw boost::bad_polymorphic_get exception"
+    );
+
+    return polymorphic_relaxed_get<U>(operand);
+}
+
+/////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// polymorphic_get<U>(variant) methods
+//
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<U>::type
+polymorphic_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return polymorphic_relaxed_get<U>(operand);
+#else
+    return polymorphic_strict_get<U>(operand);
+#endif
+
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_pointer<const U>::type
+polymorphic_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    ) BOOST_NOEXCEPT
+{
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return polymorphic_relaxed_get<U>(operand);
+#else
+    return polymorphic_strict_get<U>(operand);
+#endif
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<U>::type
+polymorphic_get(
+      boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return polymorphic_relaxed_get<U>(operand);
+#else
+    return polymorphic_strict_get<U>(operand);
+#endif
+}
+
+template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline
+    typename add_reference<const U>::type
+polymorphic_get(
+      const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand
+      BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U)
+    )
+{
+#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT
+    return polymorphic_relaxed_get<U>(operand);
+#else
+    return polymorphic_strict_get<U>(operand);
+#endif
+}
+} // namespace boost
+
+#endif // BOOST_VARIANT_POLYMORPHIC_GET_HPP

include/boost/variant/recursive_variant.hpp

@@ -116,7 +116,7 @@ struct substitute<
       BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(Arity)
     >
 {
-#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && defined(BOOST_VARIANT_USE_VARIADIC_TEMPLATES)
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
     
     typedef ::boost::variant<
         typename enable_recursive<   
@@ -131,7 +131,7 @@ struct substitute<
         >::type...  
     > type;
 
-#else
+#else // defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
 
 private: // helpers, for metafunction result (below)
 
@@ -154,7 +154,7 @@ private: // helpers, for metafunction result (below)
 public: // metafunction result
 
     typedef ::boost::variant< BOOST_VARIANT_ENUM_PARAMS(wknd_T) > type;
-#endif
+#endif // BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES workaround
 };
 
 #else // defined(BOOST_VARIANT_DETAIL_NO_SUBSTITUTE)

include/boost/variant/recursive_wrapper_fwd.hpp

@@ -15,12 +15,10 @@
 #ifndef BOOST_VARIANT_RECURSIVE_WRAPPER_FWD_HPP
 #define BOOST_VARIANT_RECURSIVE_WRAPPER_FWD_HPP
 
+#include <boost/mpl/bool.hpp>
 #include "boost/mpl/aux_/config/ctps.hpp"
-
 #include "boost/mpl/aux_/lambda_support.hpp"
-
-// should be the last #include
-#include "boost/type_traits/detail/bool_trait_def.hpp"
+#include <boost/type_traits/integral_constant.hpp>
 
 namespace boost {
 
@@ -66,11 +64,12 @@ struct is_recursive_wrapper_impl< recursive_wrapper<T> >
 
 } // namespace detail
 
-BOOST_TT_AUX_BOOL_TRAIT_DEF1(
-      is_recursive_wrapper
-    , T
-    , (::boost::detail::is_recursive_wrapper_impl<T>::value)
-    )
+template< typename T > struct is_recursive_wrapper
+    : public ::boost::integral_constant<bool,(::boost::detail::is_recursive_wrapper_impl<T>::value)>
+{
+public:
+    BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_recursive_wrapper,(T))
+};
 
 ///////////////////////////////////////////////////////////////////////////////
 // metafunction unwrap_recursive
@@ -98,6 +97,4 @@ struct unwrap_recursive< recursive_wrapper<T> >
 
 } // namespace boost
 
-#include "boost/type_traits/detail/bool_trait_undef.hpp"
-
 #endif // BOOST_VARIANT_RECURSIVE_WRAPPER_FWD_HPP

include/boost/variant/static_visitor.hpp

@@ -19,8 +19,8 @@
 #include "boost/mpl/if.hpp"
 #include "boost/type_traits/is_base_and_derived.hpp"
 
-// should be the last #include
-#include "boost/type_traits/detail/bool_trait_def.hpp"
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/mpl/aux_/lambda_support.hpp>
 
 namespace boost {
 
@@ -48,7 +48,7 @@ public: // typedefs
     typedef R result_type;
 
 protected: // for use as base class only
-#ifndef BOOST_NO_DEFAULTED_FUNCTIONS
+#if !defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS) && !defined(BOOST_NO_CXX11_NON_PUBLIC_DEFAULTED_FUNCTIONS)
     static_visitor() = default;
     ~static_visitor() = default;
 #else
@@ -83,14 +83,13 @@ struct is_static_visitor_impl
 
 } // namespace detail
 
-BOOST_TT_AUX_BOOL_TRAIT_DEF1(
-      is_static_visitor
-    , T
-    , (::boost::detail::is_static_visitor_impl<T>::value)
-    )
+template< typename T > struct is_static_visitor
+	: public ::boost::integral_constant<bool,(::boost::detail::is_static_visitor_impl<T>::value)>
+{
+public:
+    BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_static_visitor,(T))
+};
 
 } // namespace boost
 
-#include "boost/type_traits/detail/bool_trait_undef.hpp"
-
 #endif // BOOST_VARIANT_STATIC_VISITOR_HPP

include/boost/variant/variant.hpp

@@ -4,7 +4,7 @@
 //-----------------------------------------------------------------------------
 //
 // Copyright (c) 2002-2003 Eric Friedman, Itay Maman
-// Copyright (c) 2012-2013 Antony Polukhin
+// Copyright (c) 2012-2014 Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
@@ -18,9 +18,7 @@
 #include <cstddef> // for std::size_t
 #include <new> // for placement new
 
-#if !defined(BOOST_NO_TYPEID)
-#include <typeinfo> // for typeid, std::type_info
-#endif // BOOST_NO_TYPEID
+#include "boost/type_index.hpp"
 
 #include "boost/variant/detail/config.hpp"
 #include "boost/mpl/aux_/value_wknd.hpp"
@@ -50,6 +48,7 @@
 #include "boost/type_traits/add_const.hpp"
 #include "boost/type_traits/has_nothrow_constructor.hpp"
 #include "boost/type_traits/has_nothrow_copy.hpp"
+#include "boost/type_traits/is_nothrow_move_assignable.hpp"
 #include "boost/type_traits/is_nothrow_move_constructible.hpp"
 #include "boost/type_traits/is_const.hpp"
 #include "boost/type_traits/is_same.hpp"
@@ -346,20 +345,12 @@ public: // visitor interface
         return operand;
     }
 
-#if defined BOOST_MSVC 
-# pragma warning( push ) 
-# pragma warning( disable : 4702 ) // unreachable code 
-#endif 
     template <typename U>
     T& operator()(U&) const
     {
         // logical error to be here: see precondition above
-        BOOST_ASSERT(false);
         return ::boost::detail::variant::forced_return< T& >();
     }
-#if defined BOOST_MSVC 
-# pragma warning( pop ) 
-#endif
 };
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -689,10 +680,48 @@ private: // helpers, for visitor interface (below)
         new(addr) RhsT(*static_cast<const RhsT*>(obj));
     }
 
+    template <typename LhsT>
+    void backup_assign_impl(
+          backup_holder<LhsT>& lhs_content
+        , mpl::false_ // is_nothrow_move_constructible
+        , long
+        )
+    {
+        // Move lhs content to backup...
+        backup_holder<LhsT> backup_lhs_content(0);
+        backup_lhs_content.swap(lhs_content); // nothrow
+
+        // ...destroy lhs content...
+        lhs_content.~backup_holder<LhsT>(); // nothrow
+
+        BOOST_TRY
+        {
+            // ...and attempt to copy rhs content into lhs storage:
+            copy_rhs_content_(lhs_.storage_.address(), rhs_content_);
+        }
+        BOOST_CATCH (...)
+        {
+            // In case of failure, copy backup pointer to lhs storage...
+            new(lhs_.storage_.address())
+                    backup_holder<LhsT>( 0 ); // nothrow
+
+            static_cast<backup_holder<LhsT>* >(lhs_.storage_.address())
+                    ->swap(backup_lhs_content); // nothrow
+
+            // ...and rethrow:
+            BOOST_RETHROW;
+        }
+        BOOST_CATCH_END
+
+        // In case of success, indicate new content type:
+        lhs_.indicate_which(rhs_which_); // nothrow
+    }
+
     template <typename LhsT>
     void backup_assign_impl(
           LhsT& lhs_content
         , mpl::true_ // is_nothrow_move_constructible
+        , int
         )
     {
         // Move lhs content to backup...
@@ -729,6 +758,7 @@ private: // helpers, for visitor interface (below)
     void backup_assign_impl(
           LhsT& lhs_content
         , mpl::false_ // is_nothrow_move_constructible
+        , int
         )
     {
         // Backup lhs content...
@@ -772,7 +802,7 @@ public: // visitor interface
         typedef typename is_nothrow_move_constructible<LhsT>::type
             nothrow_move;
 
-        backup_assign_impl( lhs_content, nothrow_move() );
+        backup_assign_impl( lhs_content, nothrow_move(), 1L);
 
         BOOST_VARIANT_AUX_RETURN_VOID;
     }
@@ -830,23 +860,19 @@ private:
 // Generic static visitor that performs a typeid on the value it visits.
 //
 
-#if !defined(BOOST_NO_TYPEID)
-
 class reflect
-    : public static_visitor<const std::type_info&>
+    : public static_visitor<const boost::typeindex::type_info&>
 {
 public: // visitor interfaces
 
     template <typename T>
-    const std::type_info& operator()(const T&) const BOOST_NOEXCEPT
+    const boost::typeindex::type_info& operator()(const T&) const BOOST_NOEXCEPT
     {
-        return typeid(T);
+        return boost::typeindex::type_id<T>().type_info();
     }
 
 };
 
-#endif // BOOST_NO_TYPEID
-
 ///////////////////////////////////////////////////////////////////////////////
 // (detail) class comparer
 //
@@ -1326,7 +1352,10 @@ public: // structors
         destroy_content();
     }
 
-    variant() BOOST_NOEXCEPT_IF(boost::has_nothrow_constructor<internal_T0>::value)
+    variant() 
+#if !(defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, <= 0x5130))
+              BOOST_NOEXCEPT_IF(boost::has_nothrow_constructor<internal_T0>::value)
+#endif
     {
 #ifdef _MSC_VER
 #pragma warning( push )
@@ -2155,13 +2184,11 @@ public: // queries
         return false;
     }
 
-#if !defined(BOOST_NO_TYPEID)
-    const std::type_info& type() const
+    const boost::typeindex::type_info& type() const
     {
         detail::variant::reflect visitor;
         return this->apply_visitor(visitor);
     }
-#endif
 
 public: // prevent comparison with foreign types
 
@@ -2181,6 +2208,30 @@ public: // prevent comparison with foreign types
         BOOST_STATIC_ASSERT( false && sizeof(U) );
     }
 
+    template <typename U>
+    void operator!=(const U&) const
+    {
+        BOOST_STATIC_ASSERT( false && sizeof(U) );
+    }
+
+    template <typename U>
+    void operator>(const U&) const
+    {
+        BOOST_STATIC_ASSERT( false && sizeof(U) );
+    }
+
+    template <typename U>
+    void operator<=(const U&) const
+    {
+        BOOST_STATIC_ASSERT( false && sizeof(U) );
+    }
+
+    template <typename U>
+    void operator>=(const U&) const
+    {
+        BOOST_STATIC_ASSERT( false && sizeof(U) );
+    }
+
 public: // comparison operators
 
     // [MSVC6 requires these operators appear after template operators]
@@ -2211,6 +2262,28 @@ public: // comparison operators
         return rhs.apply_visitor(visitor);
     }
 
+    ///////////////////////////////////////////////////////////////////////////////
+    // comparison operators != > <= >=
+    inline bool operator!=(const variant& rhs) const
+    {
+        return !(*this == rhs);
+    }
+
+    inline bool operator>(const variant& rhs) const
+    {
+        return rhs < *this;
+    }
+
+    inline bool operator<=(const variant& rhs) const
+    {
+        return !(*this > rhs);
+    }
+
+    inline bool operator>=(const variant& rhs) const
+    {
+        return !(*this < rhs);
+    }
+
 // helpers, for visitation support (below) -- private when possible
 #if !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
 
@@ -2319,6 +2392,7 @@ public: // metafunction result
 
 };
 
+
 ///////////////////////////////////////////////////////////////////////////////
 // function template swap
 //

include/boost/variant/variant_fwd.hpp

@@ -25,16 +25,6 @@
 #include "boost/preprocessor/enum_shifted_params.hpp"
 #include "boost/preprocessor/repeat.hpp"
 
-///////////////////////////////////////////////////////////////////////////////
-// macro BOOST_VARIANT_LIMIT_TYPES
-//
-// Implementation-defined preprocessor symbol describing the actual
-// length of variant's pseudo-variadic template parameter list.
-//
-#include "boost/mpl/limits/list.hpp"
-#define BOOST_VARIANT_LIMIT_TYPES \
-    BOOST_MPL_LIMIT_LIST_SIZE
-
 ///////////////////////////////////////////////////////////////////////////////
 // macro BOOST_VARIANT_NO_REFERENCE_SUPPORT
 //
@@ -67,11 +57,36 @@
 #include "boost/variant/detail/substitute_fwd.hpp"
 
 #if defined(BOOST_VARIANT_DETAIL_NO_SUBSTITUTE) \
- && !defined(BOOST_VARIANT_NO_FULL_RECURSIVE_VARIANT_SUPPORT)
+  && !defined(BOOST_VARIANT_NO_FULL_RECURSIVE_VARIANT_SUPPORT)
 #   define BOOST_VARIANT_NO_FULL_RECURSIVE_VARIANT_SUPPORT
 #endif
 
-#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && defined(BOOST_VARIANT_USE_VARIADIC_TEMPLATES)
+
+///////////////////////////////////////////////////////////////////////////////
+// macro BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+//
+
+/* 
+    GCC before 4.0 had no variadic tempaltes; 
+    GCC 4.6 has incomplete implementation of variadic templates.
+
+    MSVC2013 has variadic templates, but they have issues.
+
+    NOTE: Clang compiler defines __GNUC__
+*/
+#if defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) \
+  || (!defined(__clang__) && defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ < 7)) \
+  || (defined(_MSC_VER) && (_MSC_VER <= 1900)) \
+  || defined(BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE) \
+  || defined (BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT)
+
+#ifndef BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+#   define BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+#endif
+
+#endif
+
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
 #include <boost/preprocessor/seq/size.hpp>
 
 #define BOOST_VARIANT_CLASS_OR_TYPENAME_TO_SEQ_class class)(
@@ -104,7 +119,7 @@
 // Rationale: Cleaner, simpler code for clients of variant library. Minimal 
 // code modifications to move from C++03 to C++11.
 //
-// Without !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && defined(BOOST_VARIANT_USE_VARIADIC_TEMPLATES)
+// With BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES defined
 // will be used BOOST_VARIANT_ENUM_PARAMS and BOOST_VARIANT_ENUM_SHIFTED_PARAMS from below `#else`
 //
 
@@ -117,7 +132,17 @@
     BOOST_VARIANT_MAKE_VARIADIC( (BOOST_VARIANT_CLASS_OR_TYPENAME_TO_SEQ_ ## x), x) \
     /**/
 
-#else 
+#else // defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+
+///////////////////////////////////////////////////////////////////////////////
+// macro BOOST_VARIANT_LIMIT_TYPES
+//
+// Implementation-defined preprocessor symbol describing the actual
+// length of variant's pseudo-variadic template parameter list.
+//
+#include "boost/mpl/limits/list.hpp"
+#define BOOST_VARIANT_LIMIT_TYPES \
+    BOOST_MPL_LIMIT_LIST_SIZE
 
 ///////////////////////////////////////////////////////////////////////////////
 // macro BOOST_VARIANT_RECURSIVE_VARIANT_MAX_ARITY
@@ -148,7 +173,8 @@
 #define BOOST_VARIANT_ENUM_SHIFTED_PARAMS( param )  \
     BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_VARIANT_LIMIT_TYPES, param)
 
-#endif // BOOST_NO_CXX11_VARIADIC_TEMPLATES
+#endif // BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES workaround
+
 
 namespace boost {
 
@@ -188,7 +214,6 @@ struct convert_void< void_ >
 //
 
 #if defined(BOOST_NO_USING_DECLARATION_OVERLOADS_FROM_TYPENAME_BASE)
-
 // (detail) tags voidNN -- NN defined on [0, BOOST_VARIANT_LIMIT_TYPES)
 //
 // Defines void types that are each unique and specializations of
@@ -217,11 +242,10 @@ BOOST_PP_REPEAT(
 
 }} // namespace detail::variant
 
-#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && defined(BOOST_VARIANT_USE_VARIADIC_TEMPLATES)
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
+#   define BOOST_VARIANT_AUX_DECLARE_PARAMS BOOST_VARIANT_ENUM_PARAMS(typename T)
+#else // defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
 
-#define BOOST_VARIANT_AUX_DECLARE_PARAMS BOOST_VARIANT_ENUM_PARAMS(typename T)
-
-#else
 ///////////////////////////////////////////////////////////////////////////////
 // (detail) macro BOOST_VARIANT_AUX_DECLARE_PARAM
 //
@@ -250,7 +274,7 @@ BOOST_PP_REPEAT(
         ) \
     /**/
 
-#endif // BOOST_NO_CXX11_VARIADIC_TEMPLATES
+#endif // BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES workaround
 
 ///////////////////////////////////////////////////////////////////////////////
 // class template variant (concept inspired by Andrei Alexandrescu)

meta/libraries.json

@@ -0,0 +1,16 @@
+{
+    "key": "variant",
+    "name": "Variant",
+    "authors": [
+        "Eric Friedman",
+        "Itay Maman"
+    ],
+    "description": "Safe, generic, stack-based discriminated union container.",
+    "category": [
+        "Containers",
+        "Data"
+    ],
+    "maintainers": [
+        "Eric Friedman <ericbrandon -at- gmail.com>"
+    ]
+}

perf/move_perf.cpp

@@ -1,4 +1,4 @@
-//  (C) Copyright Antony Polukhin 2012.
+//  (C) Copyright Antony Polukhin 2012-2014.
 //  Use, modification and distribution are 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)
@@ -75,7 +75,7 @@ static void do_test(bool do_count_cleanup_time = false) {
     {
         scope sc("boost::variant(variant&&) moving speed");
         for (std::size_t i = 0; i < c_run_count; ++i) {
-            data_to.push_back(std::move(data_from[i]));
+            data_to.push_back(boost::move(data_from[i]));
         }
 
         if (do_count_cleanup_time) {
@@ -108,7 +108,7 @@ static void do_test(bool do_count_cleanup_time = false) {
     {
         scope sc("boost::variant=(variant&&) moving speed on same types");
         for (std::size_t i = 0; i < c_run_count; ++i) {
-            data_to[i] = std::move(data_from[i]); 
+            data_to[i] = boost::move(data_from[i]); 
         }
 
         if (do_count_cleanup_time) {
@@ -142,7 +142,7 @@ static void do_test(bool do_count_cleanup_time = false) {
     {
         scope sc("boost::variant=(variant&&) moving speed on different types");
         for (std::size_t i = 0; i < c_run_count; ++i) {
-            data_to[i] = std::move(data_from[i]); 
+            data_to[i] = boost::move(data_from[i]); 
         }
 
         if (do_count_cleanup_time) {
@@ -176,7 +176,7 @@ static void do_test(bool do_count_cleanup_time = false) {
     {
         scope sc("boost::variant=(variant&&) moving speed on different types II");
         for (std::size_t i = 0; i < c_run_count; ++i) {
-            data_to[i] = std::move(data_from[i]); 
+            data_to[i] = boost::move(data_from[i]); 
         }
 
         if (do_count_cleanup_time) {
@@ -210,7 +210,7 @@ static void do_test(bool do_count_cleanup_time = false) {
     {
         scope sc("boost::variant=(T&&) moving speed");
         for (std::size_t i = 0; i < c_run_count; ++i) {
-            data_to[i] = std::move(s2[i]);
+            data_to[i] = boost::move(s2[i]);
         }
 
         if (do_count_cleanup_time) {
@@ -222,6 +222,13 @@ static void do_test(bool do_count_cleanup_time = false) {
 
 
 int main () {
+
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    std::cout << "# Running tests in C++11 mode (with rvalues).\n";
+#else
+    std::cout << "# Running tests in C++03 mode (without rvalues).\n";
+#endif
+
     do_test(false);
     do_test(true);
 }

test/Jamfile.v2

@@ -3,26 +3,14 @@
 #  Copyright (C) 2003, Eric Friedman, Itay Maman.
 #  Copyright (C) 2013, Antony Polukhin.
 #
-#  This material is provided "as is", with absolutely no warranty expressed
-#  or implied. Any use is at your own risk.
-#
-#  Permission to use or copy this software for any purpose is hereby granted
-#  without fee, provided the above notices are retained on all copies.
-#  Permission to modify the code and to distribute modified code is granted,
-#  provided the above notices are retained, and a notice that the code was
-#  modified is included with the above copyright notice.
+# 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)
 #
 project
     : requirements
         #<dependency>/boost/test//minimal
         <toolset>msvc:<asynch-exceptions>on
-        <toolset>gcc-4.8:<cxxflags>-DBOOST_VARIANT_USE_VARIADIC_TEMPLATES
-        <toolset>gcc-4.9:<cxxflags>-DBOOST_VARIANT_USE_VARIADIC_TEMPLATES
-        <toolset>clang-3.0:<cxxflags>-DBOOST_VARIANT_USE_VARIADIC_TEMPLATES
-        <toolset>clang-3.1:<cxxflags>-DBOOST_VARIANT_USE_VARIADIC_TEMPLATES
-        <toolset>clang-3.2:<cxxflags>-DBOOST_VARIANT_USE_VARIADIC_TEMPLATES
-        <toolset>clang-3.3:<cxxflags>-DBOOST_VARIANT_USE_VARIADIC_TEMPLATES
-        <toolset>clang-3.4:<cxxflags>-DBOOST_VARIANT_USE_VARIADIC_TEMPLATES
     ;
     
 test-suite variant
@@ -30,6 +18,7 @@ test-suite variant
     [ run test1.cpp class_a.cpp : : : : variant_test1 ]
     [ run test2.cpp : : : : variant_test2 ]
     [ run test3.cpp : : : : variant_test3 ]
+    [ run test3.cpp : : : <rtti>off <define>BOOST_NO_RTTI <define>BOOST_NO_TYPEID : variant_test3_no_rtti ]
     [ run test4.cpp class_a.cpp 
         : : : : variant_test4 ]
     [ run test5.cpp : : : : variant_test5 ]
@@ -40,9 +29,12 @@ test-suite variant
     [ run variant_reference_test.cpp ]
     [ run variant_comparison_test.cpp ]
     [ run variant_visit_test.cpp ]
+    [ run variant_get_test.cpp ]
+    [ run variant_polymorphic_get_test.cpp ]
     [ run variant_multivisit_test.cpp ]
     [ run hash_variant_test.cpp ]
     [ run rvalue_test.cpp ]
+    [ run variant_nonempty_check.cpp ]
     [ run recursive_variant_test.cpp : : : <define>BOOST_NO_EXCEPTIONS
       <toolset>gcc-4.3:<cxxflags>-fno-exceptions
       <toolset>gcc-4.4:<cxxflags>-fno-exceptions
@@ -53,7 +45,9 @@ test-suite variant
       <toolset>clang:<cxxflags>-fno-exceptions
       : variant_noexcept_test
     ]
+    [ run recursive_variant_test.cpp : : : <rtti>off <define>BOOST_NO_RTTI <define>BOOST_NO_TYPEID : variant_no_rtti_test ]
     [ run variant_swap_test.cpp ]
+    [ run auto_visitors.cpp ]
    ; 
 
 

test/auto_visitors.cpp

@@ -0,0 +1,380 @@
+//-----------------------------------------------------------------------------
+// boost-libs variant/test/auto_visitors.cpp source file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2014-2015 Antony Polukhin
+//
+// 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/config.hpp"
+
+#include "boost/test/minimal.hpp"
+#include "boost/variant.hpp"
+#include "boost/variant/multivisitors.hpp"
+#include "boost/lexical_cast.hpp"
+
+#include <boost/noncopyable.hpp>
+#include <boost/core/ignore_unused.hpp>
+
+namespace has_result_type_tests {
+    template <class T>
+    struct wrap {
+        typedef T result_type;
+    };
+
+    struct s1 : wrap<int> {};
+    struct s2 : wrap<int&> {};
+    struct s3 : wrap<const int&> {};
+    struct s4 {};
+    struct s5 : wrap<int*> {};
+    struct s6 : wrap<int**> {};
+    struct s7 : wrap<const int*> {};
+    struct s8 : wrap<boost::noncopyable> {};
+    struct s9 : wrap<boost::noncopyable&> {};
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    struct s10 : wrap<boost::noncopyable&&> {};
+#endif
+    struct s11 : wrap<const boost::noncopyable&> {};
+    struct s12 : wrap<const boost::noncopyable*> {};
+    struct s13 : wrap<boost::noncopyable*> {};
+    struct s14 { typedef int result_type; };
+    struct s15 { typedef int& result_type; };
+    struct s16 { typedef const int& result_type; };
+}
+
+
+void test_has_result_type_triat() {
+    using namespace has_result_type_tests;
+    using boost::detail::variant::has_result_type;
+
+    BOOST_CHECK(has_result_type<s1>::value);
+    BOOST_CHECK(has_result_type<s2>::value);
+    BOOST_CHECK(has_result_type<s3>::value);
+    BOOST_CHECK(!has_result_type<s4>::value);
+    BOOST_CHECK(has_result_type<s5>::value);
+    BOOST_CHECK(has_result_type<s6>::value);
+    BOOST_CHECK(has_result_type<s7>::value);
+    BOOST_CHECK(has_result_type<s8>::value);
+    BOOST_CHECK(has_result_type<s9>::value);
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    BOOST_CHECK(has_result_type<s10>::value);
+#endif
+    BOOST_CHECK(has_result_type<s11>::value);
+    BOOST_CHECK(has_result_type<s12>::value);
+    BOOST_CHECK(has_result_type<s13>::value);
+    BOOST_CHECK(has_result_type<s14>::value);
+    BOOST_CHECK(has_result_type<s15>::value);
+    BOOST_CHECK(has_result_type<s16>::value);
+}
+
+struct lex_streamer_explicit: boost::static_visitor<std::string> {
+    template <class T>
+    const char* operator()(const T& ) {
+        return "10";
+    }
+
+    template <class T1, class T2>
+    const char* operator()(const T1& , const T2& ) {
+        return "100";
+    }
+};
+
+
+void run_explicit()
+{
+    typedef boost::variant<int, std::string, double> variant_type;
+    variant_type v2("10"), v1("100");
+
+    lex_streamer_explicit visitor_ref;
+
+    // Must return instance of std::string
+    BOOST_CHECK(boost::apply_visitor(visitor_ref, v2).c_str() == std::string("10"));
+    BOOST_CHECK(boost::apply_visitor(visitor_ref, v2, v1).c_str() == std::string("100"));
+}
+
+
+// Most part of tests from this file require decltype(auto)
+
+#ifdef BOOST_NO_CXX14_DECLTYPE_AUTO
+
+void run()
+{
+    BOOST_CHECK(true);
+}
+
+void run2()
+{
+    BOOST_CHECK(true);
+}
+
+
+void run3()
+{
+    BOOST_CHECK(true);
+}
+
+#else
+
+#include <iostream>
+
+struct lex_streamer {
+    template <class T>
+    std::string operator()(const T& val) const {
+        return boost::lexical_cast<std::string>(val);
+    }
+};
+
+struct lex_streamer_void {
+    template <class T>
+    void operator()(const T& val) const {
+        std::cout << val << std::endl;
+    }
+
+
+    template <class T1, class T2>
+    void operator()(const T1& val, const T2& val2) const {
+        std::cout << val << '+' << val2 << std::endl;
+    }
+
+
+    template <class T1, class T2, class T3>
+    void operator()(const T1& val, const T2& val2, const T3& val3) const {
+        std::cout << val << '+' << val2 << '+' << val3 << std::endl;
+    }
+};
+
+
+struct lex_streamer2 {
+    std::string res;
+
+    template <class T>
+    const char* operator()(const T& val) const {
+        return "fail";
+    }
+
+    template <class T1, class T2>
+    const char* operator()(const T1& v1, const T2& v2) const {
+        return "fail2";
+    }
+
+
+    template <class T1, class T2, class T3>
+    const char* operator()(const T1& v1, const T2& v2, const T3& v3) const {
+        return "fail3";
+    }
+
+    template <class T>
+    std::string& operator()(const T& val) {
+        res = boost::lexical_cast<std::string>(val);
+        return res;
+    }
+
+
+    template <class T1, class T2>
+    std::string& operator()(const T1& v1, const T2& v2) {
+        res = boost::lexical_cast<std::string>(v1) + "+" + boost::lexical_cast<std::string>(v2);
+        return res;
+    }
+
+
+    template <class T1, class T2, class T3>
+    std::string& operator()(const T1& v1, const T2& v2, const T3& v3) {
+        res = boost::lexical_cast<std::string>(v1) + "+" + boost::lexical_cast<std::string>(v2) 
+            + "+" + boost::lexical_cast<std::string>(v3);
+        return res;
+    }
+};
+
+#ifndef BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+#   define BOOST_CHECK_IF_HAS_VARIADIC(x) BOOST_CHECK(x)
+#else
+#   define BOOST_CHECK_IF_HAS_VARIADIC(x) /**/
+#endif
+
+void run()
+{
+    typedef boost::variant<int, std::string, double> variant_type;
+    variant_type v1(1), v2("10"), v3(100.0);
+    lex_streamer lex_streamer_visitor;
+
+    BOOST_CHECK(boost::apply_visitor(lex_streamer(), v1) == "1");
+    BOOST_CHECK_IF_HAS_VARIADIC(boost::apply_visitor(lex_streamer_visitor)(v1) == "1");
+    BOOST_CHECK(boost::apply_visitor(lex_streamer(), v2) == "10");
+    BOOST_CHECK_IF_HAS_VARIADIC(boost::apply_visitor(lex_streamer_visitor)(v2) == "10");
+
+    #ifndef BOOST_NO_CXX14_GENERIC_LAMBDAS
+        BOOST_CHECK(boost::apply_visitor([](auto v) { return boost::lexical_cast<std::string>(v); }, v1) == "1");
+        BOOST_CHECK(boost::apply_visitor([](auto v) { return boost::lexical_cast<std::string>(v); }, v2) == "10");
+
+        // Retun type must be the same in all instances, so this code does not compile
+        //boost::variant<int, short, unsigned> v_diff_types(1);
+        //BOOST_CHECK(boost::apply_visitor([](auto v) { return v; }, v_diff_types) == 1);
+
+        boost::apply_visitor([](auto v) { std::cout << v << std::endl; }, v1);
+        boost::apply_visitor([](auto v) { std::cout << v << std::endl; }, v2);
+    #endif
+
+    lex_streamer2 visitor_ref;
+    BOOST_CHECK(boost::apply_visitor(visitor_ref, v1) == "1");
+    BOOST_CHECK(boost::apply_visitor(visitor_ref, v2) == "10");
+#ifndef BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+    std::string& ref_to_string = boost::apply_visitor(visitor_ref, v1);
+    BOOST_CHECK(ref_to_string == "1");
+#endif
+    lex_streamer_void lex_streamer_void_visitor;
+    boost::apply_visitor(lex_streamer_void(), v1);
+    boost::apply_visitor(lex_streamer_void(), v2);
+#ifndef BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+    boost::apply_visitor(lex_streamer_void_visitor)(v2);
+#endif
+
+    boost::ignore_unused(lex_streamer_visitor, visitor_ref, lex_streamer_void_visitor);
+}
+
+
+struct lex_combine {
+    template <class T1, class T2>
+    std::string operator()(const T1& v1, const T2& v2) const {
+        return boost::lexical_cast<std::string>(v1) + "+" + boost::lexical_cast<std::string>(v2);
+    }
+
+
+    template <class T1, class T2, class T3>
+    std::string operator()(const T1& v1, const T2& v2, const T3& v3) const {
+        return boost::lexical_cast<std::string>(v1) + "+" 
+                + boost::lexical_cast<std::string>(v2) + '+'
+                + boost::lexical_cast<std::string>(v3);
+    }
+};
+
+void run2()
+{
+    typedef boost::variant<int, std::string, double> variant_type;
+    variant_type v1(1), v2("10"), v3(100.0);
+    lex_combine lex_combine_visitor;
+
+    BOOST_CHECK(boost::apply_visitor(lex_combine(), v1, v2) == "1+10");
+    BOOST_CHECK(boost::apply_visitor(lex_combine(), v2, v1) == "10+1");
+    BOOST_CHECK_IF_HAS_VARIADIC(boost::apply_visitor(lex_combine_visitor)(v2, v1) == "10+1");
+
+
+    #ifndef BOOST_NO_CXX14_GENERIC_LAMBDAS
+        BOOST_CHECK(
+            boost::apply_visitor(
+                [](auto v1, auto v2) {
+                    return boost::lexical_cast<std::string>(v1) + "+"
+                        + boost::lexical_cast<std::string>(v2);
+                }
+                , v1
+                , v2
+            ) == "1+10"
+        );
+        BOOST_CHECK(
+            boost::apply_visitor(
+                [](auto v1, auto v2) {
+                    return boost::lexical_cast<std::string>(v1) + "+"
+                        + boost::lexical_cast<std::string>(v2);
+                }
+                , v2
+                , v1
+            ) == "10+1"
+        );
+
+        boost::apply_visitor([](auto v1, auto v2) { std::cout << v1 << '+' << v2 << std::endl; }, v1, v2);
+        boost::apply_visitor([](auto v1, auto v2) { std::cout << v1 << '+' << v2 << std::endl; }, v2, v1);
+    #endif
+
+
+    lex_streamer2 visitor_ref;
+    BOOST_CHECK(boost::apply_visitor(visitor_ref, v1, v2) == "1+10");
+    BOOST_CHECK(boost::apply_visitor(visitor_ref, v2, v1) == "10+1");
+#ifndef BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+    std::string& ref_to_string = boost::apply_visitor(visitor_ref)(v1, v2);
+    BOOST_CHECK(ref_to_string == "1+10");
+#endif
+
+    boost::apply_visitor(lex_streamer_void(), v1, v2);
+    boost::apply_visitor(lex_streamer_void(), v2, v1);
+
+    boost::ignore_unused(lex_combine_visitor, visitor_ref);
+}
+
+#undef BOOST_CHECK_IF_HAS_VARIADIC
+
+void run3()
+{
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
+    typedef boost::variant<int, std::string, double> variant_type;
+    variant_type v1(1), v2("10"), v3(100);
+    lex_combine lex_combine_visitor;
+
+    BOOST_CHECK(boost::apply_visitor(lex_combine(), v1, v2, v3) == "1+10+100");
+    BOOST_CHECK(boost::apply_visitor(lex_combine(), v2, v1, v3) == "10+1+100");
+    BOOST_CHECK(boost::apply_visitor(lex_combine_visitor)(v2, v1, v3) == "10+1+100");
+
+
+    #ifndef BOOST_NO_CXX14_GENERIC_LAMBDAS
+        BOOST_CHECK(
+            boost::apply_visitor(
+                [](auto v1, auto v2, auto v3) {
+                    return boost::lexical_cast<std::string>(v1) + "+"
+                        + boost::lexical_cast<std::string>(v2) + "+"
+                        + boost::lexical_cast<std::string>(v3);
+                }
+                , v1
+                , v2
+                , v3
+            ) == "1+10+100"
+        );
+        BOOST_CHECK(
+            boost::apply_visitor(
+                [](auto v1, auto v2, auto v3) {
+                    return boost::lexical_cast<std::string>(v1) + "+"
+                        + boost::lexical_cast<std::string>(v2) + "+"
+                        + boost::lexical_cast<std::string>(v3);
+                }
+                , v3
+                , v1
+                , v3
+            ) == "100+1+100"
+        );
+
+        boost::apply_visitor(
+            [](auto v1, auto v2, auto v3) { std::cout << v1 << '+' << v2 << '+' << v3 << std::endl; }, 
+            v1, v2, v3
+        );
+        boost::apply_visitor(
+            [](auto v1, auto v2, auto v3) { std::cout << v1 << '+' << v2 << '+' << v3 << std::endl; },
+            v2, v1, v3
+        );
+    #endif
+
+
+    lex_streamer2 visitor_ref;
+    BOOST_CHECK(boost::apply_visitor(visitor_ref, v1, v2) == "1+10");
+    BOOST_CHECK(boost::apply_visitor(visitor_ref)(v2, v1) == "10+1");
+    std::string& ref_to_string = boost::apply_visitor(visitor_ref, v1, v2);
+    BOOST_CHECK(ref_to_string == "1+10");
+
+    lex_streamer_void lex_streamer_void_visitor;
+    boost::apply_visitor(lex_streamer_void(), v1, v2, v1);
+    boost::apply_visitor(lex_streamer_void(), v2, v1, v1);
+    boost::apply_visitor(lex_streamer_void_visitor)(v2, v1, v1);
+#endif // !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
+}
+#endif
+
+
+int test_main(int , char* [])
+{
+    run_explicit();
+    run();
+    run2();
+    run3();
+    test_has_result_type_triat();
+
+    return 0;
+}

test/hash_variant_test.cpp

@@ -1,4 +1,4 @@
-// Copyright (c) 2011
+// Copyright (c) 2011-2014
 // Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
@@ -6,25 +6,28 @@
 // http://www.boost.org/LICENSE_1_0.txt)
 
 #include "boost/test/minimal.hpp"
-#include "boost/variant/detail/hash_variant.hpp"
 #include "boost/variant.hpp"
 #include "boost/functional/hash/hash.hpp"
 
 void run()
 {
-    typedef boost::variant<bool, int, unsigned int, double> variant_type;
-		boost::hash<variant_type> hasher;
-		
-		variant_type bool_variant1 = true;
-		variant_type bool_variant2 = false;
-		variant_type int_variant = 1;
-		variant_type float_variant = 1.0;
-		variant_type uint_variant = static_cast<unsigned int>(1);
+    typedef boost::variant<bool, int, unsigned int, char> variant_type;
+    boost::hash<variant_type> hasher;
+
+    variant_type bool_variant1 = true;
+    variant_type bool_variant2 = false;
+    variant_type int_variant = 1;
+    variant_type char_variant1 = '\1';
+    variant_type char_variant2 = '\2';
+    variant_type uint_variant = static_cast<unsigned int>(1);
 
     BOOST_CHECK(hasher(bool_variant1) != hasher(bool_variant2));
     BOOST_CHECK(hasher(bool_variant1) == hasher(bool_variant1));
     BOOST_CHECK(hasher(int_variant) != hasher(uint_variant));
-    BOOST_CHECK(hasher(float_variant) != hasher(uint_variant));
+    BOOST_CHECK(hasher(char_variant1) != hasher(uint_variant));
+    BOOST_CHECK(hasher(char_variant1) != hasher(char_variant2));
+    BOOST_CHECK(hasher(char_variant1) == hasher(char_variant1));
+    BOOST_CHECK(hasher(char_variant2) == hasher(char_variant2));
 }
 
 int test_main(int , char* [])
@@ -32,3 +35,4 @@ int test_main(int , char* [])
    run();
    return 0;
 }
+

test/jobs.h

@@ -25,6 +25,7 @@
 #include "boost/variant/apply_visitor.hpp"
 #include "boost/variant/static_visitor.hpp"
 
+#include "boost/type_index.hpp"
 #include "boost/detail/workaround.hpp"
 #if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0551))
 #    pragma warn -lvc
@@ -244,9 +245,7 @@ inline void verify(VariantType& var, spec<S>, std::string str = "")
    const VariantType& cvar = var;
 
    BOOST_CHECK(boost::apply_visitor(total_sizeof(), cvar) == sizeof(S));
-#if !defined(BOOST_NO_TYPEID)
-   BOOST_CHECK(cvar.type() == typeid(S));
-#endif
+   BOOST_CHECK(cvar.type() == boost::typeindex::type_id<S>());
 
    //
    // Check get<>()
@@ -261,7 +260,7 @@ inline void verify(VariantType& var, spec<S>, std::string str = "")
       S& r = boost::get<S>(var);
       ptr1 = &r;
    }
-   catch(boost::bad_get& )
+   catch(const boost::bad_get& )
    {
       BOOST_ERROR( "get<S> failed unexpectedly" );
    }
@@ -271,7 +270,7 @@ inline void verify(VariantType& var, spec<S>, std::string str = "")
       const S& cr = boost::get<S>(cvar);
       ptr2 = &cr;
    }
-   catch(boost::bad_get& )
+   catch(const boost::bad_get& )
    {
       BOOST_ERROR( "get<S> const failed unexpectedly" );
    }
@@ -295,9 +294,7 @@ inline void verify_not(VariantType& var, spec<S>)
 {
    const VariantType& cvar = var;
 
-#if !defined(BOOST_NO_TYPEID)
-   BOOST_CHECK(cvar.type() != typeid(S));
-#endif
+   BOOST_CHECK(cvar.type() != boost::typeindex::type_id<S>());
 
    //
    // Check get<>()
@@ -314,7 +311,7 @@ inline void verify_not(VariantType& var, spec<S>)
 
       ptr1 = &r;
    }
-   catch(boost::bad_get& )
+   catch(const boost::bad_get& )
    {
       // do nothing except pass-through
    }
@@ -326,7 +323,7 @@ inline void verify_not(VariantType& var, spec<S>)
 
       ptr2 = &cr;
    }
-   catch(boost::bad_get& )
+   catch(const boost::bad_get& )
    {
       // do nothing except pass-through
    }

test/recursive_variant_test.cpp

@@ -48,10 +48,20 @@ int main( int argc, char* argv[] )
 #include <sstream>
 #include <vector>
 #include <map>
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
+#include <tuple>
+#endif // !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
 
-struct vector_printer
+struct printer
     : boost::static_visitor<std::string>
 {
+    template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
+    std::string operator()(
+            const boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> &var) const
+    {
+        return boost::apply_visitor( printer(), var );
+    }
+
     template <typename T>
     std::string operator()(const std::vector<T>& vec) const
     {
@@ -61,13 +71,37 @@ struct vector_printer
 
         typename std::vector<T>::const_iterator it = vec.begin();
         for (; it != vec.end(); ++it)
-            ost << boost::apply_visitor( vector_printer(), *it );
+            ost << printer()( *it );
 
         ost << ") ";
 
         return ost.str();
     }
 
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
+    template <int...> struct indices {};
+    template <typename... Ts, int... Is>
+    std::string operator()(const std::tuple<Ts...>& tup, indices<Is...>) const
+    {
+        std::ostringstream ost;
+        ost << "( ";
+        int a[] = {0, (ost << printer()( std::get<Is>(tup) ), 0)... };
+        (void)a;
+        ost << ") ";
+        return ost.str();
+    }
+
+    template <int N, int... Is>
+        struct make_indices : make_indices<N-1, N-1, Is...> {};
+    template <int... Is>
+        struct make_indices<0, Is...> : indices<Is...> {};
+    template <typename... Ts>
+    std::string operator()(const std::tuple<Ts...>& tup) const
+    {
+        return printer()(tup, make_indices<sizeof...(Ts)>());
+    }
+#endif // !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
+
     template <typename T>
     std::string operator()(const T& operand) const
     {
@@ -91,11 +125,48 @@ void test_recursive_variant()
     vec1.push_back(7);
 
     var1_t var1(vec1);
-    std::string result1( boost::apply_visitor( vector_printer(), var1 ) );
+    std::string result1( printer()(var1) );
 
     std::cout << "result1: " << result1 << '\n';
     BOOST_CHECK(result1 == "( 3 5 ( 3 5 ) 7 ) ");
 
+    std::vector<var1_t> vec1_copy = vec1;
+    vec1_copy.erase(vec1_copy.begin() + 2);
+    vec1_copy.insert(vec1_copy.begin() + 2, vec1_copy);
+    var1 = vec1_copy;
+    result1 = printer()(var1);
+    std::cout << "result1+: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 ( 3 5 7 ) 7 ) ");
+
+    // Uses move construction on compilers with rvalue references support
+    result1 = printer()(
+        var1_t(
+            std::vector<var1_t>(vec1_copy)
+        )
+    );
+    std::cout << "result1++: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 ( 3 5 7 ) 7 ) ");
+
+
+    var1_t vec1_another_copy(vec1_copy);
+    vec1_copy[2].swap(vec1_another_copy);
+    result1 = printer()(
+        var1_t(vec1_copy)
+    );
+    std::cout << "result1+++1: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 ( 3 5 ( 3 5 7 ) 7 ) 7 ) ");
+
+    result1 = printer()(vec1_another_copy);
+    std::cout << "result1++2: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 7 ) ");
+
+    vec1_copy[2].swap(vec1_copy[2]);
+    result1 = printer()(
+        var1_t(vec1_copy)
+    );
+    std::cout << "result1.2: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 ( 3 5 ( 3 5 7 ) 7 ) 7 ) ");
+
     typedef boost::make_recursive_variant<
           boost::variant<int, double>
         , std::vector<boost::recursive_variant_>
@@ -108,7 +179,7 @@ void test_recursive_variant()
     vec2.push_back(boost::variant<int, double>(7));
 
     var2_t var2(vec2);
-    std::string result2( boost::apply_visitor( vector_printer(), var2 ) );
+    std::string result2( printer()(var2) );
 
     std::cout << "result2: " << result2 << '\n';
     BOOST_CHECK(result2 == "( 3 3.5 ( 3 3.5 ) 7 ) ");
@@ -135,7 +206,7 @@ void test_recursive_variant()
     vec3.push_back(7);
 
     var4_t var4(vec3);
-    std::string result3( boost::apply_visitor( vector_printer(), var4 ) );
+    std::string result3( printer()(var4) );
 
     std::cout << "result2: " << result3 << '\n';
     BOOST_CHECK(result3 == "( 3 5 ( 3.5 ( 3 5 ) ) 7 ) ");
@@ -150,7 +221,7 @@ void test_recursive_variant()
     vec5.push_back(vec1);
     vec5.push_back(17.25);
 
-    std::string result5( vector_printer()(vec5) );
+    std::string result5( printer()(vec5) );
 
     std::cout << "result5: " << result5 << '\n';
     BOOST_CHECK(result5 == "( 3.5 ( 3 5 ( 3 5 ) 7 ) 17.25 ) ");
@@ -160,6 +231,21 @@ void test_recursive_variant()
           std::map<int, boost::recursive_variant_>
         >::type var6_t;
     var6_t var6;
+
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
+    typedef boost::make_recursive_variant<
+          int,
+          std::tuple<int, boost::recursive_variant_>
+        >::type var7_t;
+    var7_t var7 = 0;
+    var7 = std::tuple<int, var7_t>(1, var7);
+    var7 = std::tuple<int, var7_t>(2, var7);
+
+    std::string result7( printer()(var7) );
+
+    std::cout << "result7: " << result7 << '\n';
+    BOOST_CHECK(result7 == "( 2 ( 1 0 ) ) ");
+#endif // !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_HDR_TUPLE)
 }
 
 void test_recursive_variant_over()
@@ -178,11 +264,41 @@ void test_recursive_variant_over()
     vec1.push_back(7);
 
     var1_t var1(vec1);
-    std::string result1( boost::apply_visitor( vector_printer(), var1 ) );
+    std::string result1( printer()(var1) );
 
     std::cout << "result1: " << result1 << '\n';
     BOOST_CHECK(result1 == "( 3 5 ( 3 5 ) 7 ) ");
 
+    std::vector<var1_t> vec1_copy = vec1;
+    vec1_copy.erase(vec1_copy.begin() + 2);
+    vec1_copy.insert(vec1_copy.begin() + 2, vec1_copy);
+    var1 = vec1_copy;
+    result1 = printer()(var1);
+    std::cout << "result1+: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 ( 3 5 7 ) 7 ) ");
+
+    // Uses move construction on compilers with rvalue references support
+    result1 = printer()(
+        var1_t(
+            std::vector<var1_t>(vec1_copy)
+        )
+    );
+    std::cout << "result1++: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 ( 3 5 7 ) 7 ) ");
+
+
+    var1_t vec1_another_copy(vec1_copy);
+    vec1_copy[2].swap(vec1_another_copy);
+    result1 = printer()(
+        var1_t(vec1_copy)
+    );
+    std::cout << "result1+++1: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 ( 3 5 ( 3 5 7 ) 7 ) 7 ) ");
+
+    result1 = printer()(vec1_another_copy);
+    std::cout << "result1++2: " << result1 << '\n';
+    BOOST_CHECK(result1 == "( 3 5 7 ) ");
+
     typedef boost::make_recursive_variant_over<
           boost::mpl::vector<
               boost::make_variant_over<boost::mpl::vector<int, double> >::type
@@ -197,7 +313,7 @@ void test_recursive_variant_over()
     vec2.push_back(boost::variant<int, double>(7));
 
     var2_t var2(vec2);
-    std::string result2( boost::apply_visitor( vector_printer(), var2 ) );
+    std::string result2( printer()(var2) );
 
     std::cout << "result2: " << result2 << '\n';
     BOOST_CHECK(result2 == "( 3 3.5 ( 3 3.5 ) 7 ) ");
@@ -235,7 +351,7 @@ void test_recursive_variant_over()
     vec3.push_back(7);
 
     var4_t var3(vec3);
-    std::string result3( boost::apply_visitor( vector_printer(), var3 ) );
+    std::string result3( printer()(var3) );
 
     std::cout << "result2: " << result3 << '\n';
     BOOST_CHECK(result3 == "( 3 5 ( 3.5 ( 3 5 ) ) 7 ) ");
@@ -252,7 +368,7 @@ void test_recursive_variant_over()
     vec5.push_back(vec1);
     vec5.push_back(17.25);
 
-    std::string result5( vector_printer()(vec5) );
+    std::string result5( printer()(vec5) );
 
     std::cout << "result5: " << result5 << '\n';
     BOOST_CHECK(result5 == "( 3.5 ( 3 5 ( 3 5 ) 7 ) 17.25 ) ");

test/rvalue_test.cpp

@@ -3,7 +3,7 @@
 // See http://www.boost.org for updates, documentation, and revision history.
 //-----------------------------------------------------------------------------
 //
-// Copyright (c) 2012-2013 Antony Polukhin
+// Copyright (c) 2012-2014 Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
@@ -14,10 +14,25 @@
 #include "boost/test/minimal.hpp"
 #include "boost/variant.hpp"
 #include "boost/type_traits/is_nothrow_move_assignable.hpp"
+#include "boost/mpl/bool.hpp"
+
+#include <boost/blank.hpp>
+#include <boost/swap.hpp>
+
+namespace swap_ambiguouty_test_ns {
+    struct A {};
+    struct B {};
+
+    void swap_ambiguouty_test() {
+        // If boost::blank is not used, then it compiles.
+        typedef boost::variant<boost::blank, A, B> Variant;
+        Variant v1, v2;
+        swap(v1, v2);
+    }
+} // namespace swap_ambiguouty_test_ns
 
 // Most part of tests from this file require rvalue references support
 
-
 class move_copy_conting_class {
 public:
     static unsigned int moves_count;
@@ -189,6 +204,13 @@ private:
     move_only_structure& operator=(const move_only_structure&);
 };
 
+struct visitor_returning_move_only_type: boost::static_visitor<move_only_structure> {
+    template <class T>
+    move_only_structure operator()(const T&) const {
+        return move_only_structure();
+    }
+};
+
 void run_move_only()
 {
     move_only_structure mo;
@@ -204,6 +226,9 @@ void run_move_only()
     vi = static_cast<move_only_structure&&>(mo);
     vi2 = static_cast<move_only_structure&&>(mo);
     BOOST_CHECK(vi.which() == 1);
+
+    move_only_structure from_visitor = boost::apply_visitor(visitor_returning_move_only_type(), vi);
+    (void)from_visitor;
 }
 
 void run_moves_are_noexcept() {
@@ -256,13 +281,43 @@ void run_tricky_compilation_test()
     v = nothrow_copyable_throw_movable();
 }
 
+template <typename T>
+struct is_container : boost::mpl::false_ {};
+
+template <typename T>
+struct is_container<boost::variant<T> > : is_container<T> {};
+
+template <BOOST_VARIANT_ENUM_PARAMS(typename T)>
+struct is_container<boost::variant<BOOST_VARIANT_ENUM_PARAMS(T)> >
+  : boost::mpl::bool_<is_container<T0>::value
+     || is_container<boost::variant<BOOST_VARIANT_ENUM_SHIFTED_PARAMS(T)> >::value>
+{};
+
+void run_is_container_compilation_test()
+{
+    BOOST_CHECK((!is_container<boost::variant<double, int> >::value));
+    BOOST_CHECK((!is_container<boost::variant<double, int, char> >::value));
+    BOOST_CHECK((!is_container<boost::variant<double, int, char, float> >::value));
+}
+
 int test_main(int , char* [])
 {
+   swap_ambiguouty_test_ns::swap_ambiguouty_test();
    run();
    run1();
    run_move_only();
    run_moves_are_noexcept();
    run_tricky_compilation_test();
    run_const_rvalues();
+   run_is_container_compilation_test();
+
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ > 6)
+#   ifdef BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES
+        BOOST_CHECK(false && 
+            "Something wrong with macro definitions. GCC-4.7+ is known to work with variadic templates"
+        );
+#   endif
+#endif
+
    return 0;
 }

test/test3.cpp

@@ -122,9 +122,7 @@ int test_main(int, char* [])
    std::ostringstream e1_str;
    e1_str << e1;
 
-#if !defined(BOOST_NO_TYPEID)
-   BOOST_CHECK(e1.type() == typeid(Add));
-#endif
+   BOOST_CHECK(e1.type() == boost::typeindex::type_id<Add>());
    BOOST_CHECK(e1_str.str() == "(13+((40+2)-(10+4)))");
 
    //Evaluate expression

test/test8.cpp

@@ -58,17 +58,17 @@ T& check_pass(Variant& v, T value)
 template <typename T, typename Variant>
 void check_fail(Variant& v)
 {
-    BOOST_CHECK(!get<T>(&v));
+    BOOST_CHECK(!relaxed_get<T>(&v));
 
     try
     {
-        T& r = get<T>(v);
+        T& r = relaxed_get<T>(v);
         (void)r; // suppress warning about r not being used
-        BOOST_CHECK(false && &r); // should never reach
+        BOOST_CHECK(false && relaxed_get<T>(&v)); // should never reach
     }
-    catch(boost::bad_get&)
+    catch(const boost::bad_get& e)
     {
-        // (do nothing here)
+        BOOST_CHECK(!!e.what()); // make sure that what() is const qualified and returnes something
     }
 }
 

test/variant_comparison_test.cpp

@@ -3,8 +3,8 @@
 // See http://www.boost.org for updates, documentation, and revision history.
 //-----------------------------------------------------------------------------
 //
-// Copyright (c) 2003
-// Eric Friedman, Itay Maman
+// Copyright (c) 2003 Eric Friedman, Itay Maman
+// Copyright (c) 2014 Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
@@ -34,6 +34,9 @@ void assert_equality_comparable(
     BOOST_CHECK( !(&x == &y) || (x == y) );
     BOOST_CHECK( !(&x == &z) || (x == z) );
     BOOST_CHECK( !(&y == &z) || (y == z) );
+    BOOST_CHECK( !(&x == &y) || !(x != y) );
+    BOOST_CHECK( !(&x == &z) || !(x != z) );
+    BOOST_CHECK( !(&y == &z) || !(y != z) );
 
     // reflexivity check
     BOOST_CHECK( (x == x) );
@@ -43,12 +46,18 @@ void assert_equality_comparable(
     // symmetry check
     BOOST_CHECK( !(x == y) || (y == x) );
     BOOST_CHECK( !(y == x) || (x == y) );
+    BOOST_CHECK( (x != y) || (y == x) );
+    BOOST_CHECK( (y != x) || (x == y) );
 
     BOOST_CHECK( !(x == z) || (z == x) );
     BOOST_CHECK( !(z == x) || (x == z) );
+    BOOST_CHECK( (x != z) || (z == x) );
+    BOOST_CHECK( (z != x) || (x == z) );
 
     BOOST_CHECK( !(y == z) || (z == y) );
     BOOST_CHECK( !(z == y) || (y == z) );
+    BOOST_CHECK( (y != z) || (z == y) );
+    BOOST_CHECK( (z != y) || (y == z) );
 
     // transitivity check
     BOOST_CHECK( !(x == y && y == z) || (x == z) );
@@ -65,12 +74,34 @@ void assert_less_than_comparable(
     BOOST_CHECK( !(x < x) );
     BOOST_CHECK( !(y < y) );
     BOOST_CHECK( !(z < z) );
+    BOOST_CHECK( !(x > x) );
+    BOOST_CHECK( !(y > y) );
+    BOOST_CHECK( !(z > z) );
+
+    BOOST_CHECK( (x <= x) );
+    BOOST_CHECK( (y <= y) );
+    BOOST_CHECK( (z <= z) );
+    BOOST_CHECK( (x >= x) );
+    BOOST_CHECK( (y >= y) );
+    BOOST_CHECK( (z >= z) );
 
     // transitivity check
     BOOST_CHECK( (x < y) );
     BOOST_CHECK( (y < z) );
     BOOST_CHECK( (x < z) );
 
+    BOOST_CHECK( (x <= y) );
+    BOOST_CHECK( (y <= z) );
+    BOOST_CHECK( (x <= z) );
+
+    BOOST_CHECK( (z > y) );
+    BOOST_CHECK( (y > x) );
+    BOOST_CHECK( (z > x) );
+
+    BOOST_CHECK( (z >= y) );
+    BOOST_CHECK( (y >= x) );
+    BOOST_CHECK( (z >= x) );
+
     // antisymmetry check
     BOOST_CHECK( !(y < x) );
     BOOST_CHECK( !(z < y) );

test/variant_get_test.cpp

@@ -0,0 +1,355 @@
+//-----------------------------------------------------------------------------
+// boost-libs variant/test/variant_get_test.cpp source file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2014-2015 Antony Polukhin
+//
+// 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/variant/get.hpp"
+#include "boost/variant/variant.hpp"
+#include "boost/variant/polymorphic_get.hpp"
+#include "boost/variant/recursive_wrapper.hpp"
+#include "boost/test/minimal.hpp"
+
+struct base {
+    int trash;
+
+    base() : trash(123) {}
+    base(const base& b) : trash(b.trash) { int i = 100; (void)i; }
+    const base& operator=(const base& b) {
+        trash = b.trash;
+        int i = 100; (void)i;
+
+        return *this;
+    }
+
+    virtual ~base(){}
+};
+
+struct derived1 : base{};
+struct derived2 : base{};
+
+struct vbase { short trash; virtual ~vbase(){} virtual int foo() const { return 0; }  };
+struct vderived1 : virtual vbase{ virtual int foo() const { return 1; } };
+struct vderived2 : virtual vbase{ virtual int foo() const { return 3; } };
+struct vderived3 : vderived1, vderived2 { virtual int foo() const { return 3; } };
+
+typedef boost::variant<int, base, derived1, derived2, std::string> var_t;
+typedef boost::variant<int, derived1, derived2, std::string> var_t_shortened;
+typedef boost::variant<base, derived1, derived2> var_t_no_fallback;
+typedef boost::variant<int&, base&, derived1&, derived2&, std::string&> var_ref_t;
+typedef boost::variant<const int&, const base&, const derived1&, const derived2&, const std::string&> var_cref_t;
+
+struct recursive_structure;
+typedef boost::variant<
+    int, base, derived1, derived2, std::string, boost::recursive_wrapper<recursive_structure>
+> var_req_t;
+struct recursive_structure { var_req_t var; };
+
+template <class T, class V, class TestType>
+inline void check_polymorphic_get_on_types_impl_single_type(V* v)
+{
+    typedef typename boost::add_reference<TestType>::type ref_test_t;
+    typedef typename boost::add_reference<const TestType>::type cref_test_t;
+    const bool exact_same = !!boost::is_same<T, TestType>::value;
+    const bool ref_same = !!boost::is_same<T, ref_test_t>::value;
+
+    if (exact_same || ref_same) {
+        BOOST_CHECK(boost::polymorphic_get<TestType>(v));
+        BOOST_CHECK(boost::polymorphic_get<const TestType>(v));
+        BOOST_CHECK(boost::polymorphic_strict_get<TestType>(v));
+        BOOST_CHECK(boost::polymorphic_strict_get<const TestType>(v));
+        BOOST_CHECK(boost::polymorphic_relaxed_get<TestType>(v));
+        BOOST_CHECK(boost::polymorphic_relaxed_get<const TestType>(v));
+    } else {
+        if (ref_same) {
+            BOOST_CHECK(boost::polymorphic_get<ref_test_t>(v));
+            BOOST_CHECK(boost::polymorphic_get<cref_test_t>(v));
+            BOOST_CHECK(boost::polymorphic_strict_get<ref_test_t>(v));
+            BOOST_CHECK(boost::polymorphic_strict_get<cref_test_t>(v));
+            BOOST_CHECK(boost::polymorphic_relaxed_get<ref_test_t>(v));
+            BOOST_CHECK(boost::polymorphic_relaxed_get<cref_test_t>(v));
+        }
+
+        BOOST_CHECK(!boost::polymorphic_get<TestType>(v));
+        BOOST_CHECK(!boost::polymorphic_get<const TestType>(v));
+        BOOST_CHECK(!boost::polymorphic_strict_get<TestType>(v));
+        BOOST_CHECK(!boost::polymorphic_strict_get<const TestType>(v));
+        BOOST_CHECK(!boost::polymorphic_relaxed_get<TestType>(v));
+        BOOST_CHECK(!boost::polymorphic_relaxed_get<const TestType>(v));
+    }
+}
+
+template <class T, class V, class TestType>
+inline void check_get_on_types_impl_single_type(V* v)
+{
+    typedef typename boost::add_reference<TestType>::type ref_test_t;
+    typedef typename boost::add_reference<const TestType>::type cref_test_t;
+    const bool exact_same = !!boost::is_same<T, TestType>::value;
+    const bool ref_same = !!boost::is_same<T, ref_test_t>::value;
+
+    if (exact_same || ref_same) {
+        BOOST_CHECK(boost::get<TestType>(v));
+        BOOST_CHECK(boost::get<const TestType>(v));
+        BOOST_CHECK(boost::strict_get<TestType>(v));
+        BOOST_CHECK(boost::strict_get<const TestType>(v));
+        BOOST_CHECK(boost::relaxed_get<TestType>(v));
+        BOOST_CHECK(boost::relaxed_get<const TestType>(v));
+
+        BOOST_CHECK(boost::get<cref_test_t>(v));
+        BOOST_CHECK(boost::strict_get<cref_test_t>(v));
+        BOOST_CHECK(boost::relaxed_get<cref_test_t>(v));
+    } else {
+        if (ref_same) {
+            BOOST_CHECK(boost::get<ref_test_t>(v));
+            BOOST_CHECK(boost::get<cref_test_t>(v));
+            BOOST_CHECK(boost::strict_get<ref_test_t>(v));
+            BOOST_CHECK(boost::strict_get<cref_test_t>(v));
+            BOOST_CHECK(boost::relaxed_get<ref_test_t>(v));
+            BOOST_CHECK(boost::relaxed_get<cref_test_t>(v));
+        }
+
+        BOOST_CHECK(!boost::get<TestType>(v));
+        BOOST_CHECK(!boost::get<const TestType>(v));
+        BOOST_CHECK(!boost::strict_get<TestType>(v));
+        BOOST_CHECK(!boost::strict_get<const TestType>(v));
+        BOOST_CHECK(!boost::relaxed_get<TestType>(v));
+        BOOST_CHECK(!boost::relaxed_get<const TestType>(v));
+    }
+}
+
+template <class T, class V>
+inline void check_get_on_types_impl(V* v)
+{
+    check_get_on_types_impl_single_type<T, V, int>(v);
+    check_polymorphic_get_on_types_impl_single_type<T, V, int>(v);
+
+    check_get_on_types_impl_single_type<T, V, base>(v);
+
+    check_get_on_types_impl_single_type<T, V, derived1>(v);
+    check_polymorphic_get_on_types_impl_single_type<T, V, derived1>(v);
+
+    check_get_on_types_impl_single_type<T, V, derived2>(v);
+    check_polymorphic_get_on_types_impl_single_type<T, V, derived2>(v);
+
+    check_get_on_types_impl_single_type<T, V, std::string>(v);
+    check_polymorphic_get_on_types_impl_single_type<T, V, std::string>(v);
+
+    // Never exist in here
+    BOOST_CHECK(!boost::relaxed_get<short>(v));
+    BOOST_CHECK(!boost::relaxed_get<const short>(v));
+    BOOST_CHECK(!boost::relaxed_get<char>(v));
+    BOOST_CHECK(!boost::relaxed_get<char*>(v));
+    BOOST_CHECK(!boost::relaxed_get<bool>(v));
+    BOOST_CHECK(!boost::relaxed_get<const bool>(v));
+
+    BOOST_CHECK(!boost::polymorphic_relaxed_get<short>(v));
+    BOOST_CHECK(!boost::polymorphic_relaxed_get<const short>(v));
+    BOOST_CHECK(!boost::polymorphic_relaxed_get<char>(v));
+    BOOST_CHECK(!boost::polymorphic_relaxed_get<char*>(v));
+    BOOST_CHECK(!boost::polymorphic_relaxed_get<bool>(v));
+    BOOST_CHECK(!boost::polymorphic_relaxed_get<const bool>(v));
+
+    boost::get<T>(*v);              // Must compile
+    boost::get<const T>(*v);        // Must compile
+    boost::strict_get<T>(*v);         // Must compile
+    boost::strict_get<const T>(*v);   // Must compile
+
+    boost::polymorphic_get<T>(*v);              // Must compile
+    boost::polymorphic_get<const T>(*v);        // Must compile
+    boost::polymorphic_strict_get<T>(*v);         // Must compile
+    boost::polymorphic_strict_get<const T>(*v);   // Must compile
+}
+
+template <class T, class V>
+inline void check_get_on_types(V* v)
+{
+    check_get_on_types_impl<T, V>(v);
+    check_get_on_types_impl<T, const V>(v);
+}
+
+inline void get_test()
+{
+    var_t v;
+    check_get_on_types<int>(&v);
+
+    var_t(base()).swap(v);
+    check_get_on_types<base>(&v);
+
+    var_t(derived1()).swap(v);
+    check_get_on_types<derived1>(&v);
+
+    var_t(derived2()).swap(v);
+    check_get_on_types<derived2>(&v);
+
+    var_t(std::string("Hello")).swap(v);
+    check_get_on_types<std::string>(&v);
+
+    var_t_shortened vs = derived2();
+    check_polymorphic_get_on_types_impl_single_type<derived2, var_t_shortened, int>(&vs);
+    check_polymorphic_get_on_types_impl_single_type<derived2, const var_t_shortened, int>(&vs);
+    // Checking that Base is really determinated
+    check_polymorphic_get_on_types_impl_single_type<base, var_t_shortened, base>(&vs);
+    check_polymorphic_get_on_types_impl_single_type<base, const var_t_shortened, base>(&vs);
+
+    vs = derived1();
+    check_polymorphic_get_on_types_impl_single_type<derived2, var_t_shortened, int>(&vs);
+    check_polymorphic_get_on_types_impl_single_type<derived2, const var_t_shortened, int>(&vs);
+    // Checking that Base is really determinated
+    check_polymorphic_get_on_types_impl_single_type<base, var_t_shortened, base>(&vs);
+    check_polymorphic_get_on_types_impl_single_type<base, const var_t_shortened, base>(&vs);
+}
+
+inline void get_test_no_fallback()
+{
+    var_t_no_fallback v;
+    var_t_no_fallback(base()).swap(v);
+    check_polymorphic_get_on_types_impl_single_type<base, var_t_no_fallback, base>(&v);
+    check_polymorphic_get_on_types_impl_single_type<base, const var_t_no_fallback, base>(&v);
+    check_get_on_types_impl_single_type<base, var_t_no_fallback, base>(&v);
+    check_get_on_types_impl_single_type<base, const var_t_no_fallback, base>(&v);
+
+    var_t_no_fallback(derived1()).swap(v);
+    check_polymorphic_get_on_types_impl_single_type<base, var_t_no_fallback, base>(&v);
+    check_polymorphic_get_on_types_impl_single_type<base, const var_t_no_fallback, base>(&v);
+    check_get_on_types_impl_single_type<derived1, var_t_no_fallback, derived1>(&v);
+    check_get_on_types_impl_single_type<derived1, const var_t_no_fallback, derived1>(&v);
+
+    var_t_no_fallback(derived2()).swap(v);
+    check_polymorphic_get_on_types_impl_single_type<base, var_t_no_fallback, base>(&v);
+    check_polymorphic_get_on_types_impl_single_type<base, const var_t_no_fallback, base>(&v);
+    check_get_on_types_impl_single_type<derived2, var_t_no_fallback, derived2>(&v);
+    check_get_on_types_impl_single_type<derived2, const var_t_no_fallback, derived2>(&v);
+}
+
+inline void get_ref_test()
+{
+    int i = 0;
+    var_ref_t v(i);
+    check_get_on_types<int>(&v);
+
+    base b;
+    var_ref_t v1(b);
+    check_get_on_types<base>(&v1);
+
+    derived1 d1;
+    var_ref_t v2(d1);
+    check_get_on_types<derived1>(&v2);
+
+    derived2 d2;
+    var_ref_t v3(d2);
+    check_get_on_types<derived2>(&v3);
+
+    std::string s("Hello");
+    var_ref_t v4(s);
+    check_get_on_types<std::string>(&v4);
+}
+
+
+inline void get_cref_test()
+{
+    int i = 0;
+    var_cref_t v(i);
+    BOOST_CHECK(boost::get<const int>(&v));
+    BOOST_CHECK(!boost::get<const base>(&v));
+
+    base b;
+    var_cref_t v1(b);
+    BOOST_CHECK(boost::get<const base>(&v1));
+    BOOST_CHECK(!boost::get<const derived1>(&v1));
+    BOOST_CHECK(!boost::get<const int>(&v1));
+
+    std::string s("Hello");
+    const var_cref_t v4 = s;
+    BOOST_CHECK(boost::get<const std::string>(&v4));
+    BOOST_CHECK(!boost::get<const int>(&v4));
+}
+
+inline void get_recursive_test()
+{
+    var_req_t v;
+    check_get_on_types<int>(&v);
+
+    var_req_t(base()).swap(v);
+    check_get_on_types<base>(&v);
+
+    var_req_t(derived1()).swap(v);
+    check_get_on_types<derived1>(&v);
+
+    var_req_t(derived2()).swap(v);
+    check_get_on_types<derived2>(&v);
+
+    var_req_t(std::string("Hello")).swap(v);
+    check_get_on_types<std::string>(&v);
+
+    recursive_structure s = { v }; // copying "v"
+    v = s;
+    check_get_on_types<recursive_structure>(&v);
+}
+
+template <class T>
+inline void check_that_does_not_exist_impl()
+{
+    using namespace boost::detail::variant;
+
+    BOOST_CHECK((holds_element<T, const int>::value));
+    BOOST_CHECK((!holds_element<T, short>::value));
+    BOOST_CHECK((!holds_element<T, short>::value));
+    BOOST_CHECK((!holds_element<T, const short>::value));
+    BOOST_CHECK((!holds_element<T, char*>::value));
+    BOOST_CHECK((!holds_element<T, const char*>::value));
+    BOOST_CHECK((!holds_element<T, char[5]>::value));
+    BOOST_CHECK((!holds_element<T, const char[5]>::value));
+    BOOST_CHECK((!holds_element<T, bool>::value));
+    BOOST_CHECK((!holds_element<T, const bool>::value));
+
+    BOOST_CHECK((!holds_element<T, boost::recursive_wrapper<int> >::value));
+    BOOST_CHECK((!holds_element<T, boost::recursive_wrapper<short> >::value));
+    BOOST_CHECK((!holds_element<T, boost::detail::reference_content<short> >::value));
+
+
+    BOOST_CHECK((holds_element_polymorphic<T, const int>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, short>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, short>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, const short>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, char*>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, const char*>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, char[5]>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, const char[5]>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, bool>::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, const bool>::value));
+
+    BOOST_CHECK((!holds_element_polymorphic<T, boost::recursive_wrapper<int> >::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, boost::recursive_wrapper<short> >::value));
+    BOOST_CHECK((!holds_element_polymorphic<T, boost::detail::reference_content<short> >::value));
+}
+
+inline void check_that_does_not_exist()
+{
+    using namespace boost::detail::variant;
+
+    BOOST_CHECK((holds_element<var_t, int>::value));
+    BOOST_CHECK((holds_element<var_ref_t, int>::value));
+    BOOST_CHECK((!holds_element<var_cref_t, int>::value));
+
+    check_that_does_not_exist_impl<var_t>();
+    check_that_does_not_exist_impl<var_ref_t>();
+    check_that_does_not_exist_impl<var_cref_t>();
+    check_that_does_not_exist_impl<var_req_t>();
+}
+
+int test_main(int , char* [])
+{
+    get_test();
+    get_test_no_fallback();
+    get_ref_test();
+    get_cref_test();
+    get_recursive_test();
+    check_that_does_not_exist();
+
+    return boost::exit_success;
+}

test/variant_multivisit_test.cpp

@@ -3,37 +3,46 @@
 // See http://www.boost.org for updates, documentation, and revision history.
 //-----------------------------------------------------------------------------
 //
-// Copyright (c) 2013
-// Antony Polukhin
+// Copyright (c) 2013-2015 Antony Polukhin
 //
 // 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/config.hpp"
+#include "boost/noncopyable.hpp"
 #define BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS 5
 #include "boost/variant/multivisitors.hpp"
+#include "boost/variant.hpp"
 
 #include "boost/test/minimal.hpp"
 
+struct my_noncopyable : boost::noncopyable {
+    my_noncopyable(){}
+    ~my_noncopyable(){}
+};
+
+typedef boost::variant<my_noncopyable, int>         variant_noncopy_t;
+
+
 typedef boost::variant<char, unsigned char, signed char, unsigned short, int, unsigned int>         variant6_t;
 
 struct test_visitor: boost::static_visitor<> {
     // operators that shall not be called
     template <class  T1, class  T2, class  T3>
-    void operator()(T1, T2, T3) const 
+    void operator()(T1&, T2&, T3&) const 
     {
         BOOST_CHECK(false);
     }
 
     template <class  T1, class  T2, class  T3, class  T4>
-    void operator()(T1, T2, T3, T4) const 
+    void operator()(T1&, T2&, T3&, T4&) const 
     {
         BOOST_CHECK(false);
     }
 
     template <class  T1, class  T2, class  T3, class  T4, class  T5>
-    void operator()(T1, T2, T3, T4, T5) const 
+    void operator()(T1&, T2&, T3&, T4&, T5&) const 
     {
         BOOST_CHECK(false);
     }
@@ -62,15 +71,30 @@ struct test_visitor: boost::static_visitor<> {
         BOOST_CHECK(v3 == 3);
         BOOST_CHECK(v4 == 4);
     }
+
+
+    // Noncopyables
+    void operator()(my_noncopyable&, my_noncopyable&, my_noncopyable&) const {
+        BOOST_CHECK(true);
+    }
+    void operator()(my_noncopyable&, my_noncopyable&, my_noncopyable&, my_noncopyable&) const {
+        BOOST_CHECK(true);
+    }
+    void operator()(my_noncopyable&, my_noncopyable&, my_noncopyable&, my_noncopyable&, my_noncopyable&) const {
+        BOOST_CHECK(true);
+    }
+    void operator()(my_noncopyable&, my_noncopyable&, my_noncopyable&, my_noncopyable&, my_noncopyable&, my_noncopyable&) const {
+        BOOST_CHECK(true);
+    }
 };
 
 typedef boost::variant<int, double, bool> bool_like_t;
 typedef boost::variant<int, double> arithmetics_t;
 
 struct if_visitor: public boost::static_visitor<arithmetics_t> {
-    template <class T1, class T2>
-    arithmetics_t operator()(bool b, T1 v1, T2 v2) const {
-        if (b) {
+    template <class T0, class T1, class T2>
+    arithmetics_t operator()(T0 b, T1 v1, T2 v2) const {
+        if (!!b) {
             return v1;
         } else {
             return v2;
@@ -112,13 +136,24 @@ int test_main(int , char* [])
         arithmetics_t(true)
     );
 
-    /* Delayed multi visitation is not implemented
+#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
     if_visitor if_vis;
     BOOST_CHECK(
         boost::apply_visitor(if_vis)(v0, v1, v2)
         ==
         arithmetics_t(true)
     );
-    */
+#endif
+
+
+    variant_noncopy_t vnonc[6];
+    boost::apply_visitor(v, vnonc[0], vnonc[1], vnonc[2]);
+    boost::apply_visitor(test_visitor(), vnonc[0], vnonc[1], vnonc[2], vnonc[3]);
+
+#ifdef BOOST_VARIANT_MULTIVISITORS_TEST_VERY_EXTREME
+    boost::apply_visitor(v, vnonc[0], vnonc[1], vnonc[2], vnonc[3], vnonc[4]);
+    boost::apply_visitor(test_visitor(), vnonc[0], vnonc[1], vnonc[2], vnonc[3], vnonc[4], vnonc[5]);
+#endif
+
     return boost::exit_success;
 }

test/variant_nonempty_check.cpp

@@ -0,0 +1,474 @@
+//-----------------------------------------------------------------------------
+// boost-libs variant/test/variant_nonempty_check.cpp source file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2014 Antony Polukhin
+//
+// 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)
+
+
+// In this file we are making tests to ensure that variant guarantees nonemptiness.
+//
+// For that purpose we create a `throwing_class`, that throws exception at a specified
+// assignment attempt. If exception was thrown during move/assignemnt operation we make sure
+// that data in variant is same as before move/assignemnt operation or that a fallback type is
+// stored in variant.
+//
+// Different nonthrowing_class'es are used to tests different variant internal policies:
+// with/without fallback type + throw/nothrow copyable + throw/nothrow movable
+
+
+#include "boost/variant/variant.hpp"
+#include "boost/variant/get.hpp"
+#include "boost/test/minimal.hpp"
+#include <stdexcept>
+
+struct exception_on_assignment : std::exception {};
+struct exception_on_move_assignment : exception_on_assignment {};
+
+void prevent_compiler_noexcept_detection() {
+    char* p = new char;
+    *p = '\0';
+    delete p;
+}
+
+
+struct throwing_class {
+    int trash;
+    enum helper_enum {
+        do_not_throw = 780,
+        throw_after_5,
+        throw_after_4,
+        throw_after_3,
+        throw_after_2,
+        throw_after_1
+    };
+
+    bool is_throw() {
+        if (trash < do_not_throw) {
+            return true;
+        }
+
+        if (trash > do_not_throw && trash <= throw_after_1) {
+            ++ trash;
+            return false;
+        }
+
+        return trash != do_not_throw;
+    }
+
+    throwing_class(int value = 123) BOOST_NOEXCEPT_IF(false) : trash(value) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    throwing_class(const throwing_class& b) BOOST_NOEXCEPT_IF(false) : trash(b.trash) {
+        if (is_throw()) {
+            throw exception_on_assignment();
+        }
+    }
+
+    const throwing_class& operator=(const throwing_class& b) BOOST_NOEXCEPT_IF(false) {
+        trash = b.trash;
+        if (is_throw()) {
+            throw exception_on_assignment();
+        }
+
+        return *this;
+    }
+
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    throwing_class(throwing_class&& b) BOOST_NOEXCEPT_IF(false) : trash(b.trash) {
+        if (is_throw()) {
+            throw exception_on_move_assignment();
+        }
+    }
+
+    const throwing_class& operator=(throwing_class&& b) BOOST_NOEXCEPT_IF(false) {
+        trash = b.trash;
+        if (is_throw()) {
+            throw exception_on_move_assignment();
+        }
+
+        return *this;
+    }
+#endif
+
+    virtual ~throwing_class() {}
+};
+
+struct nonthrowing_class {
+    int trash;
+
+    nonthrowing_class() BOOST_NOEXCEPT_IF(false) : trash(123) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    nonthrowing_class(const nonthrowing_class&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    const nonthrowing_class& operator=(const nonthrowing_class&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+        return *this;
+    }
+
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    nonthrowing_class(nonthrowing_class&&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    const nonthrowing_class& operator=(nonthrowing_class&&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+        return *this;
+    }
+#endif
+};
+
+struct nonthrowing_class2 {
+    int trash;
+
+    nonthrowing_class2() BOOST_NOEXCEPT_IF(false) : trash(123) {
+        prevent_compiler_noexcept_detection();
+    }
+};
+
+struct nonthrowing_class3 {
+    int trash;
+
+    nonthrowing_class3() BOOST_NOEXCEPT_IF(true) : trash(123) {}
+
+    nonthrowing_class3(const nonthrowing_class3&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    const nonthrowing_class3& operator=(const nonthrowing_class3&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+        return *this;
+    }
+
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    nonthrowing_class3(nonthrowing_class3&&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    const nonthrowing_class3& operator=(nonthrowing_class3&&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+        return *this;
+    }
+#endif
+};
+
+struct nonthrowing_class4 {
+    int trash;
+
+    nonthrowing_class4() BOOST_NOEXCEPT_IF(false) : trash(123) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    nonthrowing_class4(const nonthrowing_class4&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+    }
+
+    const nonthrowing_class4& operator=(const nonthrowing_class4&) BOOST_NOEXCEPT_IF(false) {
+        prevent_compiler_noexcept_detection();
+        return *this;
+    }
+
+#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+    nonthrowing_class4(nonthrowing_class4&&) BOOST_NOEXCEPT_IF(true) {
+    }
+
+    const nonthrowing_class4& operator=(nonthrowing_class4&&) BOOST_NOEXCEPT_IF(true) {
+        return *this;
+    }
+#endif
+};
+
+
+// Tests /////////////////////////////////////////////////////////////////////////////////////
+
+
+template <class Nonthrowing>
+inline void check_1_impl(int helper)
+{
+    boost::variant<throwing_class, Nonthrowing> v;
+    try {
+        v = throwing_class(helper);
+        BOOST_CHECK(!v.which());
+        BOOST_CHECK(boost::get<throwing_class>(&v));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v.which());
+        BOOST_CHECK(boost::get<throwing_class>(&v));
+    }
+
+    try {
+        throwing_class tc(helper);
+        v = tc;
+        BOOST_CHECK(!v.which());
+        BOOST_CHECK(boost::get<throwing_class>(&v));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v.which());
+        BOOST_CHECK(boost::get<throwing_class>(&v));
+    }
+}
+
+inline void check_1(int helper = 1)
+{
+    check_1_impl<nonthrowing_class>(helper);
+    check_1_impl<nonthrowing_class2>(helper);
+    check_1_impl<nonthrowing_class3>(helper);
+    check_1_impl<nonthrowing_class4>(helper);
+    check_1_impl<boost::blank>(helper);
+}
+
+template <class Nonthrowing>
+inline void check_2_impl(int helper)
+{
+    boost::variant<Nonthrowing, throwing_class> v;
+    try {
+        v = throwing_class(helper);
+        BOOST_CHECK(v.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v.which());
+        BOOST_CHECK(boost::get<Nonthrowing>(&v));
+    }
+
+    try {
+        throwing_class cl(helper);
+        v = cl;
+        BOOST_CHECK(v.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v.which());
+        BOOST_CHECK(boost::get<Nonthrowing>(&v));
+    }
+}
+
+inline void check_2(int helper = 1)
+{
+    check_2_impl<nonthrowing_class>(helper);
+    check_2_impl<nonthrowing_class2>(helper);
+    check_2_impl<nonthrowing_class3>(helper);
+    check_2_impl<nonthrowing_class4>(helper);
+    check_2_impl<boost::blank>(helper);
+}
+
+template <class Nonthrowing>
+inline void check_3_impl(int helper)
+{
+    boost::variant<Nonthrowing, throwing_class> v1, v2;
+
+    swap(v1, v2);
+    try {
+        v1 = throwing_class(helper);
+        BOOST_CHECK(v1.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v1));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v1.which());
+        BOOST_CHECK(boost::get<Nonthrowing>(&v1));
+    }
+
+
+    try {
+        v2 = throwing_class(helper);
+        BOOST_CHECK(v2.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v2));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v2.which());
+        BOOST_CHECK(boost::get<Nonthrowing>(&v2));
+    }
+
+
+    if (!v1.which() && !v2.which()) {
+        swap(v1, v2); // Make sure that two backup holders swap well
+        BOOST_CHECK(!v1.which());
+        BOOST_CHECK(boost::get<Nonthrowing>(&v1));
+        BOOST_CHECK(!v2.which());
+        BOOST_CHECK(boost::get<Nonthrowing>(&v2));
+
+        v1 = v2;
+    }
+}
+
+inline void check_3(int helper = 1)
+{
+    check_3_impl<nonthrowing_class>(helper);
+    check_3_impl<nonthrowing_class2>(helper);
+    check_3_impl<nonthrowing_class3>(helper);
+    check_3_impl<nonthrowing_class4>(helper);
+    check_3_impl<boost::blank>(helper);
+}
+
+inline void check_4(int helper = 1)
+{
+    // This one has a fallback
+    boost::variant<int, throwing_class> v1, v2;
+
+    swap(v1, v2);
+    try {
+        v1 = throwing_class(helper);
+        BOOST_CHECK(v1.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v1));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v1.which());
+        BOOST_CHECK(boost::get<int>(&v1));
+    }
+
+
+    try {
+        v2 = throwing_class(helper);
+        BOOST_CHECK(v2.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v2));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(!v2.which());
+        BOOST_CHECK(boost::get<int>(&v2));
+    }
+
+    if (!v1.which() && !v2.which()) {
+        swap(v1, v2);
+        BOOST_CHECK(!v1.which());
+        BOOST_CHECK(boost::get<int>(&v1));
+        BOOST_CHECK(!v2.which());
+        BOOST_CHECK(boost::get<int>(&v2));
+
+        v1 = v2;
+    }
+}
+
+template <class Nonthrowing>
+inline void check_5_impl(int helper)
+{
+    boost::variant<Nonthrowing, throwing_class> v1, v2;
+    throwing_class throw_not_now;
+    throw_not_now.trash = throwing_class::do_not_throw;
+    v1 = throw_not_now;
+    v2 = throw_not_now;
+
+    boost::get<throwing_class>(v1).trash = 1;
+    boost::get<throwing_class>(v2).trash = 1;
+
+    try {
+        v1 = throwing_class(helper);
+        BOOST_CHECK(v1.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v1));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(v1.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v1));
+    }
+
+    boost::get<throwing_class>(v1).trash = throwing_class::do_not_throw;
+    boost::get<throwing_class>(v2).trash = throwing_class::do_not_throw;
+    v1 = Nonthrowing();
+    v2 = Nonthrowing();
+    try {
+        v1 = throwing_class(helper);
+        BOOST_CHECK(v1.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v1));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(v1.which() == 0);
+        BOOST_CHECK(boost::get<Nonthrowing>(&v1));
+    }
+
+    int v1_type = v1.which();
+    int v2_type = v2.which();
+    try {
+        swap(v1, v2); // Make sure that backup holders swap well
+        BOOST_CHECK(v1.which() == v2_type);
+        BOOST_CHECK(v2.which() == v1_type);
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(v1.which() == v1_type);
+        BOOST_CHECK(v2.which() == v2_type);
+    }
+}
+
+
+inline void check_5(int helper = 1)
+{
+    check_5_impl<nonthrowing_class>(helper);
+    check_5_impl<nonthrowing_class2>(helper);
+    check_5_impl<nonthrowing_class3>(helper);
+    check_5_impl<nonthrowing_class4>(helper);
+    check_5_impl<boost::blank>(helper);
+}
+
+template <class Nonthrowing>
+inline void check_6_impl(int helper)
+{
+    boost::variant<Nonthrowing, throwing_class> v1, v2;
+    throwing_class throw_not_now;
+    throw_not_now.trash = throwing_class::do_not_throw;
+    v1 = throw_not_now;
+    v2 = throw_not_now;
+
+    v1 = throw_not_now;
+    v2 = throw_not_now;
+    swap(v1, v2);
+    boost::get<throwing_class>(v1).trash = 1;
+    boost::get<throwing_class>(v2).trash = 1;
+
+    v1 = throwing_class(throw_not_now);
+    v2 = v1;
+
+    v1 = Nonthrowing();
+    try {
+        throwing_class tc;
+        tc.trash = helper;
+        v1 = tc;
+        BOOST_CHECK(v1.which() == 1);
+        BOOST_CHECK(boost::get<throwing_class>(&v1));
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(v1.which() == 0);
+    }
+
+    v2 = Nonthrowing();
+    try {
+        v2 = 2;
+        BOOST_CHECK(false);
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(v2.which() == 0);
+    }
+
+    // Probably the most significant test:
+    // unsuccessful swap must preserve old values of variant
+    v1 = throw_not_now;
+    boost::get<throwing_class>(v1).trash = helper;
+    try {
+        swap(v1, v2);
+    } catch (const exception_on_assignment& /*e*/) {
+        BOOST_CHECK(v1.which() == 1);
+        BOOST_CHECK(v2.which() == 0);
+        BOOST_CHECK(boost::get<throwing_class>(v1).trash == helper);
+    }
+}
+
+
+inline void check_6(int helper = 1)
+{
+    check_6_impl<nonthrowing_class>(helper);
+    check_6_impl<nonthrowing_class2>(helper);
+    check_6_impl<nonthrowing_class3>(helper);
+    check_6_impl<nonthrowing_class4>(helper);
+    check_6_impl<boost::blank>(helper);
+}
+
+int test_main(int , char* [])
+{
+    // throwing_class::throw_after_1 + 1  => throw on first assignment/construction
+    // throwing_class::throw_after_1  => throw on second assignment/construction
+    // throwing_class::throw_after_2  => throw on third assignment/construction
+    // ...
+    for (int i = throwing_class::throw_after_1 + 1; i != throwing_class::do_not_throw; --i) {
+        check_1(i);
+        check_2(i);
+        check_3(i);
+        check_4(i);
+        check_5(i);
+        check_6(i);
+    }
+
+    return boost::exit_success;
+}

test/variant_polymorphic_get_test.cpp

@@ -0,0 +1,81 @@
+//-----------------------------------------------------------------------------
+// boost-libs variant/test/variant_plymorphic_get_test.cpp source file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2003 Eric Friedman
+// Copyright (c) 2013-2014 Antony Polukhin
+//
+// 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/variant/variant.hpp"
+#include "boost/variant/apply_visitor.hpp"
+#include "boost/variant/static_visitor.hpp"
+#include "boost/variant/polymorphic_get.hpp"
+#include "boost/test/minimal.hpp"
+
+struct base {int trash;};
+struct derived1 : base{};
+struct derived2 : base{};
+
+struct vbase { short trash; virtual ~vbase(){} virtual int foo() const { return 0; }  };
+struct vderived1 : virtual vbase{ virtual int foo() const { return 1; } };
+struct vderived2 : virtual vbase{ virtual int foo() const { return 3; } };
+struct vderived3 : vderived1, vderived2 { virtual int foo() const { return 3; } };
+
+template <class T, class Variant>
+inline void check_throws(Variant& v) {
+    try {
+        boost::polymorphic_get<T>(v);
+        BOOST_CHECK(false);
+    } catch (const boost::bad_polymorphic_get& e) {
+        BOOST_CHECK(!!e.what());
+        BOOST_CHECK(std::string(e.what()) != boost::bad_get().what());
+    }
+}
+
+int test_main(int , char* [])
+{
+    typedef boost::variant<int, base, derived1, derived2> var_t;
+
+    var_t var1;
+    BOOST_CHECK(!boost::polymorphic_get<base>(&var1));
+    check_throws<base>(var1);
+    BOOST_CHECK(!boost::polymorphic_get<const base>(&var1));
+    check_throws<base, const var_t>(var1);
+
+    var1 = derived1();
+    BOOST_CHECK(boost::polymorphic_get<base>(&var1));
+    BOOST_CHECK(boost::polymorphic_get<const base>(&var1));
+
+    derived2 d;
+    d.trash = 777;
+    var_t var2 = d;
+    BOOST_CHECK(boost::polymorphic_get<base>(var2).trash == 777);
+    BOOST_CHECK(boost::polymorphic_get<const base>(var2).trash == 777);
+
+    var2 = 777;
+    BOOST_CHECK(!boost::polymorphic_get<base>(&var2));
+    check_throws<base>(var2);
+    BOOST_CHECK(!boost::polymorphic_get<const base>(&var2));
+    check_throws<base, const var_t>(var2);
+    BOOST_CHECK(boost::polymorphic_get<int>(var2) == 777);
+    BOOST_CHECK(boost::polymorphic_get<const int>(var2) == 777);
+
+    typedef boost::variant<int, vbase, vderived1, vderived2, vderived3> vvar_t;
+
+    vvar_t v = vderived3();
+    boost::polymorphic_get<vderived3>(v).trash = 777;
+    const vvar_t& cv = v;
+    BOOST_CHECK(boost::polymorphic_get<vbase>(cv).trash == 777);
+    BOOST_CHECK(boost::polymorphic_get<const vbase>(cv).trash == 777);
+
+    BOOST_CHECK(boost::polymorphic_get<vbase>(cv).foo() == 3);
+    BOOST_CHECK(boost::polymorphic_get<vbase>(v).foo() == 3);
+    BOOST_CHECK(boost::polymorphic_get<const vbase>(cv).foo() == 3);
+    BOOST_CHECK(boost::polymorphic_get<const vbase>(v).foo() == 3);
+
+    return boost::exit_success;
+}