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  25 <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type">
  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_bimap.the_tutorial.the_collection_of_relations_type"></a><a class="link" href="the_collection_of_relations_type.html" title="The collection of relations type">The
  28       collection of relations type</a>
  29 </h3></div></div></div>
  30 <div class="toc"><dl>
  31 <dt><span class="section"><a href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.a_new_point_of_view">A
  32         new point of view</a></span></dt>
  33 <dt><span class="section"><a href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.configuration_parameters">Configuration
  34         parameters</a></span></dt>
  35 <dt><span class="section"><a href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.examples">Examples</a></span></dt>
  36 </dl></div>
  37 <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type_a_new_point_of_view">
  38 <div class="titlepage"><div><div><h4 class="title">
  39 <a name="boost_bimap.the_tutorial.the_collection_of_relations_type.a_new_point_of_view"></a><a class="link" href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.a_new_point_of_view" title="A new point of view">A
  40         new point of view</a>
  41 </h4></div></div></div>
  42 <p>
  43           Being able to change the collection type of the bimap relation view is
  44           another very important feature. Remember that this view allows the user
  45           to see the container as a group of the stored relations. This view has
  46           set semantics instead of map semantics.
  47         </p>
  48 <p>
  49           <span class="inlinemediaobject"><img src="../../images/bimap/collection.type.of.relation.png" alt="collection.type.of.relation"></span>
  50         </p>
  51 <p>
  52           By default, Boost.Bimap will base the collection type of the relation on
  53           the type of the left collection. If the left collection type is a set,
  54           then the collection type of the relation will be a set with the same order
  55           as the left view.
  56         </p>
  57 <p>
  58           In general, Boost.Bimap users will base the collection type of a relation
  59           on the type of the collection on one of the two sides. However there are
  60           times where it is useful to give this collection other constraints or simply
  61           to order it differently. The user is allowed to choose between:
  62         </p>
  63 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  64 <li class="listitem">
  65               left_based
  66             </li>
  67 <li class="listitem">
  68               right_based
  69             </li>
  70 <li class="listitem">
  71               set_of_relation&lt;&gt;
  72             </li>
  73 <li class="listitem">
  74               multiset_of_relation&lt;&gt;
  75             </li>
  76 <li class="listitem">
  77               unordered_set_of_relation&lt;&gt;
  78             </li>
  79 <li class="listitem">
  80               unordered_multiset_of_relation&lt;&gt;
  81             </li>
  82 <li class="listitem">
  83               list_of_relation
  84             </li>
  85 <li class="listitem">
  86               vector_of_relation
  87             </li>
  88 <li class="listitem">
  89               unconstrained_set_of_relation
  90             </li>
  91 </ul></div>
  92 <div class="tip"><table border="0" summary="Tip">
  93 <tr>
  94 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../../doc/src/images/tip.png"></td>
  95 <th align="left">Tip</th>
  96 </tr>
  97 <tr><td align="left" valign="top"><p>
  98             The first two options and the last produce faster bimaps, so prefer these
  99             where possible.
 100           </p></td></tr>
 101 </table></div>
 102 <p>
 103           <span class="inlinemediaobject"><img src="../../images/bimap/more.bimap.structures.png" alt="more.bimap.structures"></span>
 104         </p>
 105 <p>
 106           The collection type of relation can be used to create powerful containers.
 107           For example, if you need to maximize search speed, then the best bidirectional
 108           map possible is one that relates elements from an <code class="computeroutput"><span class="identifier">unordered_set</span></code>
 109           to another <code class="computeroutput"><span class="identifier">unordered_set</span></code>.
 110           The problem is that this container cannot be iterated. If you need to know
 111           the list of relations inside the container, you need another collection
 112           type of relation. In this case, a <code class="computeroutput"><span class="identifier">list_of_relation</span></code>
 113           is a good choice. The resulting container trades insertion and deletion
 114           time against fast search capabilities and the possibility of bidirectional
 115           iteration.
 116         </p>
 117 <p>
 118           <a href="../../../../example/mighty_bimap.cpp" target="_top">Go to source code</a>
 119         </p>
 120 <p>
 121 </p>
 122 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">iostream</span><span class="special">&gt;</span>
 123 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">string</span><span class="special">&gt;</span>
 124 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
 125 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">list_of</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
 126 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">unordered_set_of</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
 127
 128 <span class="keyword">struct</span> <span class="identifier">english</span> <span class="special">{};</span>
 129 <span class="keyword">struct</span> <span class="identifier">spanish</span> <span class="special">{};</span>
 130
 131 <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
 132 <span class="special">{</span>
 133     <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">bimaps</span><span class="special">;</span>
 134
 135     <span class="keyword">typedef</span> <span class="identifier">bimap</span>
 136     <span class="special">&lt;</span>
 137         <span class="identifier">unordered_set_of</span><span class="special">&lt;</span> <span class="identifier">tagged</span><span class="special">&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">,</span> <span class="identifier">spanish</span> <span class="special">&gt;</span> <span class="special">&gt;,</span>
 138         <span class="identifier">unordered_set_of</span><span class="special">&lt;</span> <span class="identifier">tagged</span><span class="special">&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">,</span> <span class="identifier">english</span> <span class="special">&gt;</span> <span class="special">&gt;,</span>
 139         <span class="identifier">list_of_relation</span>
 140
 141     <span class="special">&gt;</span> <span class="identifier">translator</span><span class="special">;</span>
 142
 143     <span class="identifier">translator</span> <span class="identifier">trans</span><span class="special">;</span>
 144
 145     <span class="comment">// We have to use `push_back` because the collection of relations is</span>
 146     <span class="comment">// a `list_of_relation`</span>
 147
 148     <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"hola"</span>  <span class="special">,</span><span class="string">"hello"</span>   <span class="special">)</span> <span class="special">);</span>
 149     <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"adios"</span> <span class="special">,</span><span class="string">"goodbye"</span> <span class="special">)</span> <span class="special">);</span>
 150     <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"rosa"</span>  <span class="special">,</span><span class="string">"rose"</span>    <span class="special">)</span> <span class="special">);</span>
 151     <span class="identifier">trans</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">value_type</span><span class="special">(</span><span class="string">"mesa"</span>  <span class="special">,</span><span class="string">"table"</span>   <span class="special">)</span> <span class="special">);</span>
 152
 153     <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"enter a word"</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
 154     <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">word</span><span class="special">;</span>
 155     <span class="identifier">std</span><span class="special">::</span><span class="identifier">getline</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cin</span><span class="special">,</span><span class="identifier">word</span><span class="special">);</span>
 156
 157     <span class="comment">// Search the queried word on the from index (Spanish)</span>
 158
 159     <span class="identifier">translator</span><span class="special">::</span><span class="identifier">map_by</span><span class="special">&lt;</span><span class="identifier">spanish</span><span class="special">&gt;::</span><span class="identifier">const_iterator</span> <span class="identifier">is</span>
 160         <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special">&lt;</span><span class="identifier">spanish</span><span class="special">&gt;().</span><span class="identifier">find</span><span class="special">(</span><span class="identifier">word</span><span class="special">);</span>
 161
 162     <span class="keyword">if</span><span class="special">(</span> <span class="identifier">is</span> <span class="special">!=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special">&lt;</span><span class="identifier">spanish</span><span class="special">&gt;().</span><span class="identifier">end</span><span class="special">()</span> <span class="special">)</span>
 163     <span class="special">{</span>
 164         <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">word</span> <span class="special">&lt;&lt;</span> <span class="string">" is said "</span>
 165                   <span class="special">&lt;&lt;</span> <span class="identifier">is</span><span class="special">-&gt;</span><span class="identifier">get</span><span class="special">&lt;</span><span class="identifier">english</span><span class="special">&gt;()</span>
 166                   <span class="special">&lt;&lt;</span> <span class="string">" in English"</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
 167     <span class="special">}</span>
 168     <span class="keyword">else</span>
 169     <span class="special">{</span>
 170         <span class="comment">// Word not found in Spanish, try our luck in English</span>
 171
 172         <span class="identifier">translator</span><span class="special">::</span><span class="identifier">map_by</span><span class="special">&lt;</span><span class="identifier">english</span><span class="special">&gt;::</span><span class="identifier">const_iterator</span> <span class="identifier">ie</span>
 173             <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special">&lt;</span><span class="identifier">english</span><span class="special">&gt;().</span><span class="identifier">find</span><span class="special">(</span><span class="identifier">word</span><span class="special">);</span>
 174
 175         <span class="keyword">if</span><span class="special">(</span> <span class="identifier">ie</span> <span class="special">!=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">by</span><span class="special">&lt;</span><span class="identifier">english</span><span class="special">&gt;().</span><span class="identifier">end</span><span class="special">()</span> <span class="special">)</span>
 176         <span class="special">{</span>
 177             <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">word</span> <span class="special">&lt;&lt;</span> <span class="string">" is said "</span>
 178                       <span class="special">&lt;&lt;</span> <span class="identifier">ie</span><span class="special">-&gt;</span><span class="identifier">get</span><span class="special">&lt;</span><span class="identifier">spanish</span><span class="special">&gt;()</span>
 179                       <span class="special">&lt;&lt;</span> <span class="string">" in Spanish"</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
 180         <span class="special">}</span>
 181         <span class="keyword">else</span>
 182         <span class="special">{</span>
 183             <span class="comment">// Word not found, show the possible translations</span>
 184
 185             <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"No such word in the dictionary"</span>      <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
 186             <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"These are the possible translations"</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
 187
 188             <span class="keyword">for</span><span class="special">(</span> <span class="identifier">translator</span><span class="special">::</span><span class="identifier">const_iterator</span>
 189                     <span class="identifier">i</span> <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span>
 190                     <span class="identifier">i_end</span> <span class="special">=</span> <span class="identifier">trans</span><span class="special">.</span><span class="identifier">end</span><span class="special">();</span>
 191
 192                     <span class="identifier">i</span> <span class="special">!=</span> <span class="identifier">i_end</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">i</span> <span class="special">)</span>
 193             <span class="special">{</span>
 194                 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">i</span><span class="special">-&gt;</span><span class="identifier">get</span><span class="special">&lt;</span><span class="identifier">spanish</span><span class="special">&gt;()</span>
 195                           <span class="special">&lt;&lt;</span> <span class="string">" &lt;---&gt; "</span>
 196                           <span class="special">&lt;&lt;</span> <span class="identifier">i</span><span class="special">-&gt;</span><span class="identifier">get</span><span class="special">&lt;</span><span class="identifier">english</span><span class="special">&gt;()</span>
 197                           <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
 198             <span class="special">}</span>
 199         <span class="special">}</span>
 200     <span class="special">}</span>
 201     <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
 202 <span class="special">}</span>
 203 </pre>
 204 <p>
 205         </p>
 206 </div>
 207 <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type_configuration_parameters">
 208 <div class="titlepage"><div><div><h4 class="title">
 209 <a name="boost_bimap.the_tutorial.the_collection_of_relations_type.configuration_parameters"></a><a class="link" href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.configuration_parameters" title="Configuration parameters">Configuration
 210         parameters</a>
 211 </h4></div></div></div>
 212 <p>
 213           Each collection type of relation has different parameters to control its
 214           behaviour. For example, in the <code class="computeroutput"><span class="identifier">set_of_relation</span></code>
 215           specification, you can pass a Functor type that compares two types. All
 216           of the parameters are exactly as in the standard library containers, except
 217           for the type, which is set to the bimap relation and the allocator type.
 218           To help users in the creation of each functor, the collection type of relation
 219           templates takes an mpl lambda expression where the relation type will be
 220           evaluated later. A placeholder named <code class="computeroutput"><span class="identifier">_relation</span></code>
 221           is available to bimap users.
 222         </p>
 223 <p>
 224           The following table lists the meaning of the parameters for each collection
 225           type of relations.
 226         </p>
 227 <div class="informaltable"><table class="table">
 228 <colgroup>
 229 <col>
 230 <col>
 231 </colgroup>
 232 <thead><tr>
 233 <th>
 234                   <p>
 235                     name
 236                   </p>
 237                 </th>
 238 <th>
 239                   <p>
 240                     Additional Parameters
 241                   </p>
 242                 </th>
 243 </tr></thead>
 244 <tbody>
 245 <tr>
 246 <td>
 247                   <p>
 248                     <code class="computeroutput"><span class="identifier">left_based</span></code>
 249                   </p>
 250                 </td>
 251 <td>
 252                   <p>
 253                     Not a template.
 254                   </p>
 255                 </td>
 256 </tr>
 257 <tr>
 258 <td>
 259                   <p>
 260                     <code class="computeroutput"><span class="identifier">right_based</span></code>
 261                   </p>
 262                 </td>
 263 <td>
 264                   <p>
 265                     Not a template.
 266                   </p>
 267                 </td>
 268 </tr>
 269 <tr>
 270 <td>
 271                   <p>
 272                     <code class="computeroutput"><span class="identifier">set_of_relation</span><span class="special">&lt;</span><span class="identifier">KeyComp</span><span class="special">&gt;</span></code>
 273                   </p>
 274                   <p>
 275                     <code class="computeroutput"><span class="identifier">multiset_of_relation</span><span class="special">&lt;</span><span class="identifier">KeyComp</span><span class="special">&gt;</span></code>
 276                   </p>
 277                 </td>
 278 <td>
 279                   <p>
 280                     <span class="bold"><strong>KeyComp </strong></span> is a Functor that compares
 281                     two types using less than. By default, the less-than operator
 282                     is <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span><span class="special">&lt;</span><span class="identifier">_relation</span><span class="special">&gt;</span></code>.
 283                   </p>
 284                 </td>
 285 </tr>
 286 <tr>
 287 <td>
 288                   <p>
 289                     <code class="computeroutput"><span class="identifier">unordered_set_of_relation</span><span class="special">&lt;</span><span class="identifier">HashFunctor</span><span class="special">,</span><span class="identifier">EqualKey</span><span class="special">&gt;</span></code>
 290                   </p>
 291                   <p>
 292                     <code class="computeroutput"><span class="identifier">unordered_multiset_of_relation</span><span class="special">&lt;</span><span class="identifier">HashFunctor</span><span class="special">,</span><span class="identifier">EqualKey</span><span class="special">&gt;</span></code>
 293                   </p>
 294                 </td>
 295 <td>
 296                   <p>
 297                     <span class="bold"><strong>HashFunctor </strong></span> converts the <code class="computeroutput"><span class="identifier">relation</span></code> into an <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span></code> value. By default it
 298                     is <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">hash</span><span class="special">&lt;</span><span class="identifier">_relation</span><span class="special">&gt;</span></code>.
 299                   </p>
 300                   <p>
 301                     <span class="bold"><strong>EqualKey </strong></span> is a Functor that
 302                     tests two relations for equality. By default, the equality operator
 303                     is <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">equal_to</span><span class="special">&lt;</span><span class="identifier">_relation</span><span class="special">&gt;</span></code>.
 304                   </p>
 305                 </td>
 306 </tr>
 307 <tr>
 308 <td>
 309                   <p>
 310                     <code class="computeroutput"><span class="identifier">list_of_relation</span></code>
 311                   </p>
 312                 </td>
 313 <td>
 314                   <p>
 315                     Not a template.
 316                   </p>
 317                 </td>
 318 </tr>
 319 <tr>
 320 <td>
 321                   <p>
 322                     <code class="computeroutput"><span class="identifier">vector_of_relation</span></code>
 323                   </p>
 324                 </td>
 325 <td>
 326                   <p>
 327                     Not a template.
 328                   </p>
 329                 </td>
 330 </tr>
 331 <tr>
 332 <td>
 333                   <p>
 334                     <code class="computeroutput"><span class="identifier">unconstrained_set_of_relation</span></code>
 335                   </p>
 336                 </td>
 337 <td>
 338                   <p>
 339                     Not a template.
 340                   </p>
 341                 </td>
 342 </tr>
 343 </tbody>
 344 </table></div>
 345 </div>
 346 <div class="section boost_bimap_the_tutorial_the_collection_of_relations_type_examples">
 347 <div class="titlepage"><div><div><h4 class="title">
 348 <a name="boost_bimap.the_tutorial.the_collection_of_relations_type.examples"></a><a class="link" href="the_collection_of_relations_type.html#boost_bimap.the_tutorial.the_collection_of_relations_type.examples" title="Examples">Examples</a>
 349 </h4></div></div></div>
 350 <p>
 351           Consider this example:
 352         </p>
 353 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span> <span class="keyword">class</span> <span class="identifier">Rel</span> <span class="special">&gt;</span>
 354 <span class="keyword">struct</span> <span class="identifier">RelOrder</span>
 355 <span class="special">{</span>
 356     <span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">Rel</span> <span class="identifier">ra</span><span class="special">,</span> <span class="identifier">Rel</span> <span class="identifier">rb</span><span class="special">)</span> <span class="keyword">const</span>
 357     <span class="special">{</span>
 358         <span class="keyword">return</span> <span class="special">(</span><span class="identifier">ra</span><span class="special">.</span><span class="identifier">left</span><span class="special">+</span><span class="identifier">ra</span><span class="special">.</span><span class="identifier">right</span><span class="special">)</span> <span class="special">&lt;</span> <span class="special">(</span><span class="identifier">rb</span><span class="special">.</span><span class="identifier">left</span><span class="special">+</span><span class="identifier">rb</span><span class="special">.</span><span class="identifier">right</span><span class="special">);</span>
 359     <span class="special">}</span>
 360 <span class="special">};</span>
 361
 362 <span class="keyword">typedef</span> <span class="identifier">bimap</span>
 363 <span class="special">&lt;</span>
 364         <span class="identifier">multiset_of</span><span class="special">&lt;</span> <span class="keyword">int</span> <span class="special">&gt;,</span>
 365         <span class="identifier">multiset_of</span><span class="special">&lt;</span> <span class="keyword">int</span> <span class="special">&gt;,</span>
 366         <span class="identifier">set_of_relation</span><span class="special">&lt;</span> <span class="identifier">RelOrder</span><span class="special">&lt;</span><span class="identifier">_relation</span><span class="special">&gt;</span> <span class="special">&gt;</span>
 367
 368 <span class="special">&gt;</span> <span class="identifier">bimap_type</span><span class="special">;</span>
 369 </pre>
 370 <p>
 371           Here the bimap relation view is ordered using the information of both sides.
 372           This container will only allow unique relations because <code class="computeroutput"><span class="identifier">set_of_relation</span></code>
 373           has been used but the elements in each side of the bimap can be repeated.
 374         </p>
 375 <pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">name</span>         <span class="special">{};</span>
 376 <span class="keyword">struct</span> <span class="identifier">phone_number</span> <span class="special">{};</span>
 377
 378 <span class="keyword">typedef</span> <span class="identifier">bimap</span>
 379 <span class="special">&lt;</span>
 380     <span class="identifier">tagged</span><span class="special">&lt;</span> <span class="identifier">unordered_multiset_of</span><span class="special">&lt;</span> <span class="identifier">string</span> <span class="special">&gt;,</span> <span class="identifier">name</span>         <span class="special">&gt;,</span>
 381     <span class="identifier">tagged</span><span class="special">&lt;</span> <span class="identifier">unordered_set_of</span>     <span class="special">&lt;</span> <span class="keyword">int</span>    <span class="special">&gt;,</span> <span class="identifier">phone_number</span> <span class="special">&gt;,</span>
 382     <span class="identifier">set_of_relation</span><span class="special">&lt;&gt;</span>
 383
 384 <span class="special">&gt;</span> <span class="identifier">bimap_type</span><span class="special">;</span>
 385 </pre>
 386 <p>
 387           In this other case the bimap will relate names to phone numbers. Names
 388           can be repeated and phone numbers are unique. You can perform quick searches
 389           by name or phone number and the container can be viewed ordered using the
 390           relation view.
 391         </p>
 392 </div>
 393 </div>
 394 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 395 <td align="left"></td>
 396 <td align="right"><div class="copyright-footer">Copyright &#169; 2006-2012 Matias Capeletto<p>
 397         Distributed under the Boost Software License, Version 1.0. (See accompanying
 398         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
 399       </p>
 400 </div></td>
 401 </tr></table>
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