1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>Reference</title> 6<link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> 7<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 8<link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> 9<link rel="up" href="../variant.html" title="Chapter 45. Boost.Variant"> 10<link rel="prev" href="tutorial.html" title="Tutorial"> 11<link rel="next" href="../BOOST_VARIANT_LIMIT_TYPES.html" title="Macro BOOST_VARIANT_LIMIT_TYPES"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../boost.png"></td> 16<td align="center"><a href="../../../index.html">Home</a></td> 17<td align="center"><a href="../../../libs/libraries.htm">Libraries</a></td> 18<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 19<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 20<td align="center"><a href="../../../more/index.htm">More</a></td> 21</tr></table> 22<hr> 23<div class="spirit-nav"> 24<a accesskey="p" href="tutorial.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../variant.html"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="../BOOST_VARIANT_LIMIT_TYPES.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="section"> 27<div class="titlepage"><div><div><h2 class="title" style="clear: both"> 28<a name="variant.reference"></a>Reference</h2></div></div></div> 29<div class="toc"><dl class="toc"> 30<dt><span class="section"><a href="reference.html#variant.concepts">Concepts</a></span></dt> 31<dt><span class="section"><a href="reference.html#header.boost.variant_hpp">Header <boost/variant.hpp></a></span></dt> 32<dt><span class="section"><a href="reference.html#header.boost.variant.variant_fwd_hpp">Header <boost/variant/variant_fwd.hpp></a></span></dt> 33<dt><span class="section"><a href="reference.html#header.boost.variant.variant_hpp">Header <boost/variant/variant.hpp></a></span></dt> 34<dt><span class="section"><a href="reference.html#header.boost.variant.recursive_variant_hpp">Header <boost/variant/recursive_variant.hpp></a></span></dt> 35<dt><span class="section"><a href="reference.html#header.boost.variant.recursive_wrapper_hpp">Header <boost/variant/recursive_wrapper.hpp></a></span></dt> 36<dt><span class="section"><a href="reference.html#header.boost.variant.apply_visitor_hpp">Header <boost/variant/apply_visitor.hpp></a></span></dt> 37<dt><span class="section"><a href="reference.html#header.boost.variant.multivisitors_hpp">Header <boost/variant/multivisitors.hpp></a></span></dt> 38<dt><span class="section"><a href="reference.html#header.boost.variant.get_hpp">Header <boost/variant/get.hpp></a></span></dt> 39<dt><span class="section"><a href="reference.html#header.boost.variant.polymorphic_get_hpp">Header <boost/variant/polymorphic_get.hpp></a></span></dt> 40<dt><span class="section"><a href="reference.html#header.boost.variant.bad_visit_hpp">Header <boost/variant/bad_visit.hpp></a></span></dt> 41<dt><span class="section"><a href="reference.html#header.boost.variant.static_visitor_hpp">Header <boost/variant/static_visitor.hpp></a></span></dt> 42<dt><span class="section"><a href="reference.html#header.boost.variant.visitor_ptr_hpp">Header <boost/variant/visitor_ptr.hpp></a></span></dt> 43</dl></div> 44<div class="section"> 45<div class="titlepage"><div><div><h3 class="title"> 46<a name="variant.concepts"></a>Concepts</h3></div></div></div> 47<div class="toc"><dl class="toc"> 48<dt><span class="section"><a href="reference.html#variant.concepts.bounded-type"><span class="emphasis"><em>BoundedType</em></span></a></span></dt> 49<dt><span class="section"><a href="reference.html#variant.concepts.static-visitor"><span class="emphasis"><em>StaticVisitor</em></span></a></span></dt> 50<dt><span class="section"><a href="reference.html#variant.concepts.output-streamable"><span class="emphasis"><em>OutputStreamable</em></span></a></span></dt> 51<dt><span class="section"><a href="reference.html#variant.concepts.hashable"><span class="emphasis"><em>Hashable</em></span></a></span></dt> 52</dl></div> 53<div class="section"> 54<div class="titlepage"><div><div><h4 class="title"> 55<a name="variant.concepts.bounded-type"></a><span class="emphasis"><em>BoundedType</em></span> 56</h4></div></div></div> 57<p>The requirements on a <span class="bold"><strong>bounded type</strong></span> 58 are as follows:</p> 59<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 60<li class="listitem"> 61<a class="link" href="../CopyConstructible.html" title="Concept CopyConstructible">CopyConstructible</a> or MoveConstructible.</li> 62<li class="listitem">Destructor upholds the no-throw exception-safety 63 guarantee.</li> 64<li class="listitem">Complete at the point of <code class="computeroutput">variant</code> template 65 instantiation. (See 66 <code class="computeroutput"><a class="link" href="../boost/recursive_wrapper.html" title="Class template recursive_wrapper">boost::recursive_wrapper</a><T></code> 67 for a type wrapper that accepts incomplete types to enable recursive 68 <code class="computeroutput">variant</code> types.)</li> 69</ul></div> 70<p>Every type specified as a template argument to 71 <code class="computeroutput"><a class="link" href="../boost/variant.html" title="Class template variant">variant</a></code> must at minimum fulfill the 72 above requirements. In addition, certain features of <code class="computeroutput">variant</code> 73 are available only if its bounded types meet the requirements of these 74 following additional concepts:</p> 75<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 76<li class="listitem"> 77<a class="link" href="../Assignable.html" title="Concept Assignable">Assignable</a>: 78 <code class="computeroutput">variant</code> is itself <span class="emphasis"><em>Assignable</em></span> if and 79 only if every one of its bounded types meets the requirements of the 80 concept. (Note that top-level <code class="computeroutput">const</code>-qualified types and 81 reference types do <span class="emphasis"><em>not</em></span> meet these 82 requirements.)</li> 83<li class="listitem">MoveAssignable: 84 <code class="computeroutput">variant</code> is itself <span class="emphasis"><em>MoveAssignable</em></span> if and 85 only if every one of its bounded types meets the requirements of the 86 concept. (Note that top-level <code class="computeroutput">const</code>-qualified types and 87 reference types do <span class="emphasis"><em>not</em></span> meet these 88 requirements.)</li> 89<li class="listitem"> 90<a class="link" href="../DefaultConstructible.html" title="Concept DefaultConstructible">DefaultConstructible</a> [20.1.4]: 91 <code class="computeroutput">variant</code> is itself 92 <a class="link" href="../DefaultConstructible.html" title="Concept DefaultConstructible">DefaultConstructible</a> if and only if its first 93 bounded type (i.e., <code class="computeroutput">T1</code>) meets the requirements of the 94 concept.</li> 95<li class="listitem"> 96<a class="link" href="../EqualityComparable.html" title="Concept EqualityComparable">EqualityComparable</a>: 97 <code class="computeroutput">variant</code> is itself <a class="link" href="../EqualityComparable.html" title="Concept EqualityComparable">EqualityComparable</a> 98 if and only if every one of its bounded types meets the requirements 99 of the concept.</li> 100<li class="listitem"> 101<a class="link" href="../LessThanComparable.html" title="Concept LessThanComparable">LessThanComparable</a>: 102 <code class="computeroutput">variant</code> is itself <a class="link" href="../LessThanComparable.html" title="Concept LessThanComparable">LessThanComparable</a> 103 if and only if every one of its bounded types meets the requirements 104 of the concept.</li> 105<li class="listitem"> 106<a class="link" href="reference.html#variant.concepts.output-streamable" title="OutputStreamable"><span class="emphasis"><em>OutputStreamable</em></span></a>: 107 <code class="computeroutput">variant</code> is itself <span class="emphasis"><em>OutputStreamable</em></span> 108 if and only if every one of its bounded types meets the requirements 109 of the concept.</li> 110<li class="listitem"> 111<a class="link" href="reference.html#variant.concepts.hashable" title="Hashable"><span class="emphasis"><em>Hashable</em></span></a>: 112 <code class="computeroutput">variant</code> is itself <span class="emphasis"><em>Hashable</em></span> 113 if and only if every one of its bounded types meets the requirements 114 of the concept.</li> 115</ul></div> 116</div> 117<div class="section"> 118<div class="titlepage"><div><div><h4 class="title"> 119<a name="variant.concepts.static-visitor"></a><span class="emphasis"><em>StaticVisitor</em></span> 120</h4></div></div></div> 121<div class="toc"><dl class="toc"><dt><span class="section"><a href="reference.html#variant.concepts.static-visitor.examples">Examples</a></span></dt></dl></div> 122<p>The requirements on a <span class="bold"><strong>static 123 visitor</strong></span> of a type <code class="computeroutput">T</code> are as follows:</p> 124<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 125<li class="listitem">Must allow invocation as a function by overloading 126 <code class="computeroutput">operator()</code>, unambiguously accepting any value of type 127 <code class="computeroutput">T</code>.</li> 128<li class="listitem">Must expose inner type <code class="computeroutput">result_type</code>. C++14 compatible compilers 129 could detect <code class="computeroutput">result_type</code> automatically, but will stick to 130 <code class="computeroutput">result_type</code> if it is defined. (See 131 <code class="computeroutput"><a class="link" href="../boost/visitor_ptr.html" title="Function template visitor_ptr">boost::visitor_ptr</a></code> for a 132 solution to using functions as visitors.)</li> 133<li class="listitem">If <code class="computeroutput">result_type</code> is not <code class="computeroutput">void</code>, then 134 each operation of the function object must return a value implicitly 135 convertible to <code class="computeroutput">result_type</code>.</li> 136</ul></div> 137<div class="section"> 138<div class="titlepage"><div><div><h5 class="title"> 139<a name="variant.concepts.static-visitor.examples"></a>Examples</h5></div></div></div> 140<p>The following class satisfies the requirements of a static visitor 141 of several types (i.e., explicitly: <code class="computeroutput">int</code> and 142 <code class="computeroutput">std::string</code>; or, e.g., implicitly: <code class="computeroutput">short</code> and 143 <code class="computeroutput">const char *</code>; etc.):</p> 144<pre class="programlisting">class my_visitor 145 : public <code class="computeroutput"><a class="link" href="../boost/static_visitor.html" title="Class template static_visitor">boost::static_visitor</a></code><int> 146{ 147public: 148 149 int operator()(int i) 150 { 151 return i * 2; 152 } 153 154 int operator()(const std::string& s) 155 { 156 return s.length(); 157 } 158 159};</pre> 160<p>Another example is the following class, whose function-call 161 operator is a member template, allowing it to operate on values of many 162 types. Thus, the following class is a visitor of any type that supports 163 streaming output (e.g., <code class="computeroutput">int</code>, <code class="computeroutput">double</code>, 164 <code class="computeroutput">std::string</code>, etc.):</p> 165<pre class="programlisting">class printer 166 : public <code class="computeroutput"><a class="link" href="../boost/static_visitor.html" title="Class template static_visitor">boost::static_visitor</a></code><> 167{ 168 template <typename T> 169 void operator()(const T& t) 170 { 171 std::cout << t << std::endl; 172 } 173};</pre> 174<p>C++14 compatible compilers detect <code class="computeroutput">result_type</code> automatically:</p> 175<pre class="programlisting"> 176 <code class="computeroutput"><a class="link" href="../boost/variant.html" title="Class template variant">boost::variant</a></code><int, float> v; 177 // ... 178 179 <code class="computeroutput"><a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor">boost::apply_visitor</a></code>( 180 [](auto val) { return std::to_string(val); }, 181 v 182 ); 183</pre> 184</div> 185</div> 186<div class="section"> 187<div class="titlepage"><div><div><h4 class="title"> 188<a name="variant.concepts.output-streamable"></a><span class="emphasis"><em>OutputStreamable</em></span> 189</h4></div></div></div> 190<p>The requirements on an <span class="bold"><strong>output 191 streamable</strong></span> type <code class="computeroutput">T</code> are as follows:</p> 192<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">For any object <code class="computeroutput">t</code> of type <code class="computeroutput">T</code>, 193 <code class="computeroutput">std::cout << t</code> must be a valid 194 expression.</li></ul></div> 195</div> 196<div class="section"> 197<div class="titlepage"><div><div><h4 class="title"> 198<a name="variant.concepts.hashable"></a><span class="emphasis"><em>Hashable</em></span> 199</h4></div></div></div> 200<p>The requirements on an <span class="bold"><strong>hashable</strong></span> type <code class="computeroutput">T</code> are as follows:</p> 201<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">For any object <code class="computeroutput">t</code> of type <code class="computeroutput">T</code>, 202 <code class="computeroutput">boost::hash<T>()(t)</code> must be a valid 203 expression.</li></ul></div> 204</div> 205</div> 206<div class="section"> 207<div class="titlepage"><div><div><h3 class="title"> 208<a name="header.boost.variant_hpp"></a>Header <<a href="../../../boost/variant.hpp" target="_top">boost/variant.hpp</a>></h3></div></div></div> 209<div class="toc"><dl class="toc"><dt><span class="section"><a href="reference.html#variant.header.include-all"></a></span></dt></dl></div> 210<div class="section"> 211<div class="titlepage"></div> 212<p>This header exists simply as a convenience to the user, including 213 all of the headers in the <code class="computeroutput">boost/variant</code> directory except <boost/multivisiors.hpp>.</p> 214</div> 215</div> 216<div class="section"> 217<div class="titlepage"><div><div><h3 class="title"> 218<a name="header.boost.variant.variant_fwd_hpp"></a>Header <<a href="../../../boost/variant/variant_fwd.hpp" target="_top">boost/variant/variant_fwd.hpp</a>></h3></div></div></div> 219<p>Provides forward declarations of the 220 <code class="computeroutput"><a class="link" href="../boost/variant.html" title="Class template variant">boost::variant</a></code>, 221 <code class="computeroutput"><a class="link" href="../boost/make_variant_over.html" title="Class template make_variant_over">boost::make_variant_over</a></code>, 222 <code class="computeroutput"><a class="link" href="../boost/make_recursive_variant.html" title="Class template make_recursive_variant">boost::make_recursive_variant</a></code>, and 223 <code class="computeroutput"><a class="link" href="../boost/make_recurs_1_3_46_5_5_1_3.html" title="Class template make_recursive_variant_over">boost::make_recursive_variant_over</a></code> 224 class templates and the <code class="computeroutput">boost::recursive_variant_</code> tag type. 225 Also defines several preprocessor symbols, as described below.</p> 226<pre class="synopsis"> 227 228<a class="link" href="../BOOST_VARIANT_LIMIT_TYPES.html" title="Macro BOOST_VARIANT_LIMIT_TYPES">BOOST_VARIANT_LIMIT_TYPES</a> 229<a class="link" href="../BOOST_VARIANT_1_3_46_5_3_4.html" title="Macro BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES">BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES</a> 230<a class="link" href="../BOOST_VARIANT_ENUM_PARAMS.html" title="Macro BOOST_VARIANT_ENUM_PARAMS">BOOST_VARIANT_ENUM_PARAMS</a>(param) 231<a class="link" href="../BOOST_VARIANT_1_3_46_5_3_6.html" title="Macro BOOST_VARIANT_ENUM_SHIFTED_PARAMS">BOOST_VARIANT_ENUM_SHIFTED_PARAMS</a>(param) 232<a class="link" href="../BOOST_VARIANT_1_3_46_5_3_7.html" title="Macro BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT">BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT</a> 233<a class="link" href="../BOOST_VARIANT_1_3_46_5_3_8.html" title="Macro BOOST_VARIANT_DO_NOT_SPECIALIZE_STD_HASH">BOOST_VARIANT_DO_NOT_SPECIALIZE_STD_HASH</a> 234<a class="link" href="../BOOST_VARIANT_1_3_46_5_3_9.html" title="Macro BOOST_VARIANT_NO_FULL_RECURSIVE_VARIANT_SUPPORT">BOOST_VARIANT_NO_FULL_RECURSIVE_VARIANT_SUPPORT</a></pre> 235</div> 236<div class="section"> 237<div class="titlepage"><div><div><h3 class="title"> 238<a name="header.boost.variant.variant_hpp"></a>Header <<a href="../../../boost/variant/variant.hpp" target="_top">boost/variant/variant.hpp</a>></h3></div></div></div> 239<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 240 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2 <span class="special">=</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> 241 <span class="keyword">typename</span> TN <span class="special">=</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span><span class="special">></span> 242 <span class="keyword">class</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special">;</span> 243 244 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Sequence<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/make_variant_over.html" title="Class template make_variant_over">make_variant_over</a><span class="special">;</span> 245 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 246 <span class="keyword">void</span> <a class="link" href="../boost/swap_1_3_46_5_4_1_2.html" title="Function template swap"><span class="identifier">swap</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">,</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 247 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> ElemType<span class="special">,</span> <span class="keyword">typename</span> Traits<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> 248 <span class="keyword">typename</span> TN<span class="special">></span> 249 <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special"><</span><span class="identifier">ElemType</span><span class="special">,</span><span class="identifier">Traits</span><span class="special">></span> <span class="special">&</span> 250 <a class="link" href="../boost/operator_1_3_46_5_4_1_3.html" title="Function template operator<<"><span class="keyword">operator</span><span class="special"><<</span></a><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special"><</span><span class="identifier">ElemType</span><span class="special">,</span><span class="identifier">Traits</span><span class="special">></span> <span class="special">&</span><span class="special">,</span> 251 <span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 252 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 253 <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <a class="link" href="../boost/hash_value_1_3_46_5_4_1_4.html" title="Function template hash_value"><span class="identifier">hash_value</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 254<span class="special">}</span></pre> 255</div> 256<div class="section"> 257<div class="titlepage"><div><div><h3 class="title"> 258<a name="header.boost.variant.recursive_variant_hpp"></a>Header <<a href="../../../boost/variant/recursive_variant.hpp" target="_top">boost/variant/recursive_variant.hpp</a>></h3></div></div></div> 259<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 260 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <a name="boost.recursive_variant_"></a><span class="identifier">recursive_variant_</span><span class="special">;</span> 261 262 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2 <span class="special">=</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> 263 <span class="keyword">typename</span> TN <span class="special">=</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span><span class="special">></span> 264 <span class="keyword">class</span> <a class="link" href="../boost/make_recursive_variant.html" title="Class template make_recursive_variant">make_recursive_variant</a><span class="special">;</span> 265 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Sequence<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/make_recurs_1_3_46_5_5_1_3.html" title="Class template make_recursive_variant_over">make_recursive_variant_over</a><span class="special">;</span> 266<span class="special">}</span></pre> 267</div> 268<div class="section"> 269<div class="titlepage"><div><div><h3 class="title"> 270<a name="header.boost.variant.recursive_wrapper_hpp"></a>Header <<a href="../../../boost/variant/recursive_wrapper.hpp" target="_top">boost/variant/recursive_wrapper.hpp</a>></h3></div></div></div> 271<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 272 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/recursive_wrapper.html" title="Class template recursive_wrapper">recursive_wrapper</a><span class="special">;</span> 273 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/is_recursive_wrapper.html" title="Class template is_recursive_wrapper">is_recursive_wrapper</a><span class="special">;</span> 274 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/unwrap_recursive_wrapper.html" title="Class template unwrap_recursive_wrapper">unwrap_recursive_wrapper</a><span class="special">;</span> 275<span class="special">}</span></pre> 276</div> 277<div class="section"> 278<div class="titlepage"><div><div><h3 class="title"> 279<a name="header.boost.variant.apply_visitor_hpp"></a>Header <<a href="../../../boost/variant/apply_visitor.hpp" target="_top">boost/variant/apply_visitor.hpp</a>></h3></div></div></div> 280<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 281 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Visitor<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/apply_visitor_delayed_t.html" title="Class template apply_visitor_delayed_t">apply_visitor_delayed_t</a><span class="special">;</span> 282 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Visitor<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/apply_visit_1_3_46_5_7_1_2.html" title="Class template apply_visitor_delayed_cpp14_t">apply_visitor_delayed_cpp14_t</a><span class="special">;</span> 283 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Visitor<span class="special">,</span> <span class="keyword">typename</span> Variant<span class="special">></span> 284 <span class="keyword">typename</span> <span class="identifier">Visitor</span><span class="special">::</span><span class="identifier">result_type</span> <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="identifier">Visitor</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">Variant</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 285 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Visitor<span class="special">,</span> <span class="keyword">typename</span> Variant<span class="special">></span> 286 <span class="keyword">typename</span> <span class="identifier">Visitor</span><span class="special">::</span><span class="identifier">result_type</span> <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">Visitor</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">Variant</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 287 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> BinaryVisitor<span class="special">,</span> <span class="keyword">typename</span> Variant1<span class="special">,</span> <span class="keyword">typename</span> Variant2<span class="special">></span> 288 <span class="keyword">typename</span> <span class="identifier">BinaryVisitor</span><span class="special">::</span><span class="identifier">result_type</span> <span class="identifier">OR</span> <span class="keyword">decltype</span><span class="special">(</span><span class="keyword">auto</span><span class="special">)</span> 289 <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="identifier">BinaryVisitor</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">Variant1</span><span class="special">&&</span><span class="special">,</span> <span class="identifier">Variant2</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 290 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> BinaryVisitor<span class="special">,</span> <span class="keyword">typename</span> Variant1<span class="special">,</span> <span class="keyword">typename</span> Variant2<span class="special">></span> 291 <span class="keyword">typename</span> <span class="identifier">BinaryVisitor</span><span class="special">::</span><span class="identifier">result_type</span> <span class="identifier">OR</span> <span class="keyword">decltype</span><span class="special">(</span><span class="keyword">auto</span><span class="special">)</span> 292 <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">BinaryVisitor</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">Variant1</span><span class="special">&&</span><span class="special">,</span> <span class="identifier">Variant2</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 293 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> MultiVisitor<span class="special">,</span> <span class="keyword">typename</span> Variant1<span class="special">,</span> <span class="keyword">typename</span> Variant2<span class="special">,</span> 294 <span class="keyword">typename</span> Variant3<span class="special">></span> 295 <span class="keyword">typename</span> <span class="identifier">MultiVisitor</span><span class="special">::</span><span class="identifier">result_type</span> <span class="identifier">OR</span> <span class="keyword">decltype</span><span class="special">(</span><span class="keyword">auto</span><span class="special">)</span> 296 <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="identifier">MultiVisitor</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">Variant1</span><span class="special">&&</span><span class="special">,</span> <span class="identifier">Variant2</span><span class="special">&&</span><span class="special">,</span> <span class="identifier">Variant3</span><span class="special">&&</span><span class="special">,</span> <span class="special">...</span><span class="special">)</span><span class="special">;</span> 297 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> MultiVisitor<span class="special">,</span> <span class="keyword">typename</span> Variant1<span class="special">,</span> <span class="keyword">typename</span> Variant2<span class="special">,</span> 298 <span class="keyword">typename</span> Variant3<span class="special">></span> 299 <span class="keyword">typename</span> <span class="identifier">MultiVisitor</span><span class="special">::</span><span class="identifier">result_type</span> <span class="identifier">OR</span> <span class="keyword">decltype</span><span class="special">(</span><span class="keyword">auto</span><span class="special">)</span> 300 <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">MultiVisitor</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">Variant1</span><span class="special">&&</span><span class="special">,</span> <span class="identifier">Variant2</span><span class="special">&&</span><span class="special">,</span> <span class="identifier">Variant3</span><span class="special">&&</span><span class="special">,</span> 301 <span class="special">...</span><span class="special">)</span><span class="special">;</span> 302 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Visitor<span class="special">></span> 303 <a class="link" href="../boost/apply_visitor_delayed_t.html" title="Class template apply_visitor_delayed_t">apply_visitor_delayed_t</a><span class="special"><</span><span class="identifier">Visitor</span><span class="special">></span> <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="identifier">Visitor</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 304 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Visitor<span class="special">></span> 305 <a class="link" href="../boost/apply_visit_1_3_46_5_7_1_2.html" title="Class template apply_visitor_delayed_cpp14_t">apply_visitor_delayed_cpp14_t</a><span class="special"><</span><span class="identifier">Visitor</span><span class="special">></span> <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor"><span class="identifier">apply_visitor</span></a><span class="special">(</span><span class="identifier">Visitor</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 306<span class="special">}</span></pre> 307</div> 308<div class="section"> 309<div class="titlepage"><div><div><h3 class="title"> 310<a name="header.boost.variant.multivisitors_hpp"></a>Header <<a href="../../../boost/variant/multivisitors.hpp" target="_top">boost/variant/multivisitors.hpp</a>></h3></div></div></div> 311<p>Provides declarations of <a class="link" href="../boost/apply_visitor.html" title="Function apply_visitor">apply_visitor</a> for three or more 312 <code class="computeroutput"><a class="link" href="../boost/variant.html" title="Class template variant">variant</a></code> parameters.</p> 313<pre class="synopsis"> 314 315<a class="link" href="../BOOST_VARAINT_1_3_46_5_8_3.html" title="Macro BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS">BOOST_VARAINT_MAX_MULTIVIZITOR_PARAMS</a></pre> 316<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 317 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> MultiVisitor<span class="special">,</span> <span class="keyword">typename</span> Variant1<span class="special">,</span> <span class="keyword">typename</span> Variant2<span class="special">,</span> 318 <span class="keyword">typename</span> Variant3<span class="special">></span> 319 <span class="keyword">typename</span> <span class="identifier">MultiVisitor</span><span class="special">::</span><span class="identifier">result_type</span> <span class="identifier">OR</span> <span class="keyword">decltype</span><span class="special">(</span><span class="keyword">auto</span><span class="special">)</span> 320 <a class="link" href="../boost/apply_visit_1_3_46_5_8_4_1.html" title="Function apply_visitor /*three or more variant parameters*/"><span class="identifier">apply_visitor</span> <span class="comment">/*three or more variant parameters*/</span></a><span class="special">(</span><span class="identifier">MultiVisitor</span> <span class="special">&</span><span class="special">,</span> 321 <span class="identifier">Variant1</span><span class="special">&&</span><span class="special">,</span> 322 <span class="identifier">Variant2</span><span class="special">&&</span><span class="special">,</span> 323 <span class="identifier">Variant3</span><span class="special">&&</span><span class="special">,</span> <span class="special">...</span><span class="special">)</span><span class="special">;</span> 324 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> MultiVisitor<span class="special">,</span> <span class="keyword">typename</span> Variant1<span class="special">,</span> <span class="keyword">typename</span> Variant2<span class="special">,</span> 325 <span class="keyword">typename</span> Variant3<span class="special">></span> 326 <span class="keyword">typename</span> <span class="identifier">MultiVisitor</span><span class="special">::</span><span class="identifier">result_type</span> <span class="identifier">OR</span> <span class="keyword">decltype</span><span class="special">(</span><span class="keyword">auto</span><span class="special">)</span> 327 <a class="link" href="../boost/apply_visit_1_3_46_5_8_4_1.html" title="Function apply_visitor /*three or more variant parameters*/"><span class="identifier">apply_visitor</span> <span class="comment">/*three or more variant parameters*/</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">MultiVisitor</span> <span class="special">&</span><span class="special">,</span> 328 <span class="identifier">Variant1</span><span class="special">&&</span><span class="special">,</span> 329 <span class="identifier">Variant2</span><span class="special">&&</span><span class="special">,</span> 330 <span class="identifier">Variant3</span><span class="special">&&</span><span class="special">,</span> <span class="special">...</span><span class="special">)</span><span class="special">;</span> 331<span class="special">}</span></pre> 332</div> 333<div class="section"> 334<div class="titlepage"><div><div><h3 class="title"> 335<a name="header.boost.variant.get_hpp"></a>Header <<a href="../../../boost/variant/get.hpp" target="_top">boost/variant/get.hpp</a>></h3></div></div></div> 336<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 337 <span class="keyword">class</span> <a class="link" href="../boost/bad_get.html" title="Class bad_get">bad_get</a><span class="special">;</span> 338 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 339 <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/relaxed_get.html" title="Function relaxed_get"><span class="identifier">relaxed_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 340 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 341 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/relaxed_get.html" title="Function relaxed_get"><span class="identifier">relaxed_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 342 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 343 <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/relaxed_get.html" title="Function relaxed_get"><span class="identifier">relaxed_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 344 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 345 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/relaxed_get.html" title="Function relaxed_get"><span class="identifier">relaxed_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 346 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 347 <span class="identifier">U</span> <span class="special">&&</span> <a class="link" href="../boost/relaxed_get.html" title="Function relaxed_get"><span class="identifier">relaxed_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&&</span><span class="special">)</span><span class="special">;</span> 348 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 349 <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/strict_get.html" title="Function strict_get"><span class="identifier">strict_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 350 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 351 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/strict_get.html" title="Function strict_get"><span class="identifier">strict_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 352 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 353 <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/strict_get.html" title="Function strict_get"><span class="identifier">strict_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 354 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 355 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/strict_get.html" title="Function strict_get"><span class="identifier">strict_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 356 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 357 <span class="identifier">U</span> <span class="special">&&</span> <a class="link" href="../boost/strict_get.html" title="Function strict_get"><span class="identifier">strict_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&&</span><span class="special">)</span><span class="special">;</span> 358 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 359 <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/get.html" title="Function get"><span class="identifier">get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 360 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 361 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/get.html" title="Function get"><span class="identifier">get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 362 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 363 <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/get.html" title="Function get"><span class="identifier">get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 364 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 365 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/get.html" title="Function get"><span class="identifier">get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 366 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 367 <span class="identifier">U</span> <span class="special">&&</span> <a class="link" href="../boost/get.html" title="Function get"><span class="identifier">get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&&</span><span class="special">)</span><span class="special">;</span> 368<span class="special">}</span></pre> 369</div> 370<div class="section"> 371<div class="titlepage"><div><div><h3 class="title"> 372<a name="header.boost.variant.polymorphic_get_hpp"></a>Header <<a href="../../../boost/variant/polymorphic_get.hpp" target="_top">boost/variant/polymorphic_get.hpp</a>></h3></div></div></div> 373<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 374 <span class="keyword">class</span> <a class="link" href="../boost/bad_polymorphic_get.html" title="Class bad_polymorphic_get">bad_polymorphic_get</a><span class="special">;</span> 375 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 376 <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/polymorphic_relaxed_get.html" title="Function polymorphic_relaxed_get"><span class="identifier">polymorphic_relaxed_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 377 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 378 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/polymorphic_relaxed_get.html" title="Function polymorphic_relaxed_get"><span class="identifier">polymorphic_relaxed_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 379 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 380 <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/polymorphic_relaxed_get.html" title="Function polymorphic_relaxed_get"><span class="identifier">polymorphic_relaxed_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 381 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 382 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/polymorphic_relaxed_get.html" title="Function polymorphic_relaxed_get"><span class="identifier">polymorphic_relaxed_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 383 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 384 <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/polymorphic_strict_get.html" title="Function polymorphic_strict_get"><span class="identifier">polymorphic_strict_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 385 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 386 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/polymorphic_strict_get.html" title="Function polymorphic_strict_get"><span class="identifier">polymorphic_strict_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 387 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 388 <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/polymorphic_strict_get.html" title="Function polymorphic_strict_get"><span class="identifier">polymorphic_strict_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 389 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 390 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/polymorphic_strict_get.html" title="Function polymorphic_strict_get"><span class="identifier">polymorphic_strict_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 391 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 392 <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/polymorphic_get.html" title="Function polymorphic_get"><span class="identifier">polymorphic_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 393 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 394 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">*</span> <a class="link" href="../boost/polymorphic_get.html" title="Function polymorphic_get"><span class="identifier">polymorphic_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">*</span><span class="special">)</span><span class="special">;</span> 395 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 396 <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/polymorphic_get.html" title="Function polymorphic_get"><span class="identifier">polymorphic_get</span></a><span class="special">(</span><a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 397 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> U<span class="special">,</span> <span class="keyword">typename</span> T1<span class="special">,</span> <span class="keyword">typename</span> T2<span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="keyword">typename</span> TN<span class="special">></span> 398 <span class="keyword">const</span> <span class="identifier">U</span> <span class="special">&</span> <a class="link" href="../boost/polymorphic_get.html" title="Function polymorphic_get"><span class="identifier">polymorphic_get</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="../boost/variant.html" title="Class template variant">variant</a><span class="special"><</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="special">...</span><span class="special">,</span> <span class="identifier">TN</span><span class="special">></span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 399<span class="special">}</span></pre> 400</div> 401<div class="section"> 402<div class="titlepage"><div><div><h3 class="title"> 403<a name="header.boost.variant.bad_visit_hpp"></a>Header <<a href="../../../boost/variant/bad_visit.hpp" target="_top">boost/variant/bad_visit.hpp</a>></h3></div></div></div> 404<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 405 <span class="keyword">class</span> <a class="link" href="../boost/bad_visit.html" title="Class bad_visit">bad_visit</a><span class="special">;</span> 406<span class="special">}</span></pre> 407</div> 408<div class="section"> 409<div class="titlepage"><div><div><h3 class="title"> 410<a name="header.boost.variant.static_visitor_hpp"></a>Header <<a href="../../../boost/variant/static_visitor.hpp" target="_top">boost/variant/static_visitor.hpp</a>></h3></div></div></div> 411<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 412 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> ResultType<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/static_visitor.html" title="Class template static_visitor">static_visitor</a><span class="special">;</span> 413<span class="special">}</span></pre> 414</div> 415<div class="section"> 416<div class="titlepage"><div><div><h3 class="title"> 417<a name="header.boost.variant.visitor_ptr_hpp"></a>Header <<a href="../../../boost/variant/visitor_ptr.hpp" target="_top">boost/variant/visitor_ptr.hpp</a>></h3></div></div></div> 418<pre class="synopsis"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> 419 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">,</span> <span class="keyword">typename</span> R<span class="special">></span> <span class="keyword">class</span> <a class="link" href="../boost/visitor_ptr_t.html" title="Class template visitor_ptr_t">visitor_ptr_t</a><span class="special">;</span> 420 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> R<span class="special">,</span> <span class="keyword">typename</span> T<span class="special">></span> <a class="link" href="../boost/visitor_ptr_t.html" title="Class template visitor_ptr_t">visitor_ptr_t</a><span class="special"><</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">R</span><span class="special">></span> <a class="link" href="../boost/visitor_ptr.html" title="Function template visitor_ptr"><span class="identifier">visitor_ptr</span></a><span class="special">(</span><span class="identifier">R</span> <span class="special">(</span><span class="special">*</span><span class="special">)</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span><span class="special">)</span><span class="special">;</span> 421<span class="special">}</span></pre> 422</div> 423</div> 424<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 425<td align="left"></td> 426<td align="right"><div class="copyright-footer">Copyright © 2002, 2003 Eric Friedman, Itay Maman<br>Copyright © 2014-2020 Antony Polukhin<p>Distributed under the Boost Software License, Version 1.0. 427 (See accompanying file <code class="filename">LICENSE_1_0.txt</code> or copy at 428 <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 429 </p> 430</div></td> 431</tr></table> 432<hr> 433<div class="spirit-nav"> 434<a accesskey="p" href="tutorial.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../variant.html"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="../BOOST_VARIANT_LIMIT_TYPES.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> 435</div> 436</body> 437</html> 438
