ceph/src/boost/libs/bimap/doc/html/boost_bimap/the_tutorial/differences_with_standard_maps.html

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  25 <div class="section boost_bimap_the_tutorial_differences_with_standard_maps">
  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_bimap.the_tutorial.differences_with_standard_maps"></a><a class="link" href="differences_with_standard_maps.html" title="Differences with standard maps">Differences
  28       with standard maps</a>
  29 </h3></div></div></div>
  30 <div class="toc"><dl>
  31 <dt><span class="section"><a href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.insertion">Insertion</a></span></dt>
  32 <dt><span class="section"><a href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.iterator__value_type">iterator::value_type</a></span></dt>
  33 <dt><span class="section"><a href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.operator_____and_at__">operator[]
  34         and at()</a></span></dt>
  35 <dt><span class="section"><a href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.complexity_of_operations">Complexity
  36         of operations</a></span></dt>
  37 </dl></div>
  38 <div class="section boost_bimap_the_tutorial_differences_with_standard_maps_insertion">
  39 <div class="titlepage"><div><div><h4 class="title">
  40 <a name="boost_bimap.the_tutorial.differences_with_standard_maps.insertion"></a><a class="link" href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.insertion" title="Insertion">Insertion</a>
  41 </h4></div></div></div>
  42 <p>
  43           Remember that a map can be interpreted as a relation between two collections.
  44           In bimaps we have the freedom to change both collection types, imposing
  45           constrains in each of them. Some insertions that we give for granted to
  46           success in standard maps fails with bimaps. For example:
  47         </p>
  48 <pre class="programlisting"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">bm</span><span class="special">;</span>
  49
  50 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="string">"orange"</span><span class="special">);</span>
  51 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">2</span><span class="special">,</span><span class="string">"orange"</span><span class="special">);</span> <span class="comment">// No effect! returns make_pair(iter,false)</span>
  52 </pre>
  53 <p>
  54           The insertion will only succeed if it is allowed by all views of the <code class="computeroutput"><span class="identifier">bimap</span></code>. In the next snippet we define
  55           the right collection as a multiset, when we try to insert the same two
  56           elements the second insertion is allowed by the left map view because both
  57           values are different and it is allowed by the right map view because it
  58           is a non-unique collection type.
  59         </p>
  60 <pre class="programlisting"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span> <span class="identifier">multiset_of</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">bm</span><span class="special">;</span>
  61
  62 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="string">"orange"</span><span class="special">);</span>
  63 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">2</span><span class="special">,</span><span class="string">"orange"</span><span class="special">);</span> <span class="comment">// Insertion succeed!</span>
  64 </pre>
  65 <p>
  66           If we use a custom collection of relation type, the insertion has to be
  67           allowed by it too.
  68         </p>
  69 </div>
  70 <div class="section boost_bimap_the_tutorial_differences_with_standard_maps_iterator__value_type">
  71 <div class="titlepage"><div><div><h4 class="title">
  72 <a name="boost_bimap.the_tutorial.differences_with_standard_maps.iterator__value_type"></a><a class="link" href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.iterator__value_type" title="iterator::value_type">iterator::value_type</a>
  73 </h4></div></div></div>
  74 <p>
  75           The relations stored in the Bimap will not be in most cases modifiable
  76           directly by iterators because both sides are used as keys of <span class="emphasis"><em>key-based</em></span>
  77           sets. When a <code class="computeroutput"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span><span class="identifier">B</span><span class="special">&gt;</span></code> left view iterator is dereferenced
  78           the return type is <span class="emphasis"><em>signature-compatible</em></span> with a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span> <span class="keyword">const</span> <span class="identifier">A</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">B</span> <span class="special">&gt;</span></code>.
  79           However there are some collection types that are not <span class="emphasis"><em>key_based</em></span>,
  80           for example list_of. If a Bimap uses one of these collection types there
  81           is no problem with modifying the data of that side. The following code
  82           is valid:
  83         </p>
  84 <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special">&lt;</span> <span class="keyword">int</span><span class="special">,</span> <span class="identifier">list_of</span><span class="special">&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">bm_type</span><span class="special">;</span>
  85 <span class="identifier">bm_type</span> <span class="identifier">bm</span><span class="special">;</span>
  86 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">relation</span><span class="special">(</span> <span class="number">1</span><span class="special">,</span> <span class="string">"one"</span> <span class="special">)</span> <span class="special">);</span>
  87 <span class="special">...</span>
  88 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">.</span><span class="identifier">find</span><span class="special">(</span><span class="number">1</span><span class="special">)-&gt;</span><span class="identifier">second</span> <span class="special">=</span> <span class="string">"1"</span><span class="special">;</span> <span class="comment">// Valid</span>
  89 </pre>
  90 <p>
  91           In this case, when the iterator is dereferenced the return type is <span class="emphasis"><em>signature-compatible</em></span>
  92           with a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">int</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span></code>.
  93         </p>
  94 <p>
  95           The following table shows the constness of the dereferenced data of each
  96           collection type of:
  97         </p>
  98 <div class="informaltable"><table class="table">
  99 <colgroup>
 100 <col>
 101 <col>
 102 </colgroup>
 103 <thead><tr>
 104 <th>
 105                   <p>
 106                     Side collection type
 107                   </p>
 108                 </th>
 109 <th>
 110                   <p>
 111                     Dereferenced data
 112                   </p>
 113                 </th>
 114 </tr></thead>
 115 <tbody>
 116 <tr>
 117 <td>
 118                   <p>
 119                     <code class="computeroutput"><span class="identifier">set_of</span></code>
 120                   </p>
 121                 </td>
 122 <td>
 123                   <p>
 124                     <span class="emphasis"><em>constant</em></span>
 125                   </p>
 126                 </td>
 127 </tr>
 128 <tr>
 129 <td>
 130                   <p>
 131                     <code class="computeroutput"><span class="identifier">multiset_of</span></code>
 132                   </p>
 133                 </td>
 134 <td>
 135                   <p>
 136                     <span class="emphasis"><em>constant</em></span>
 137                   </p>
 138                 </td>
 139 </tr>
 140 <tr>
 141 <td>
 142                   <p>
 143                     <code class="computeroutput"><span class="identifier">unordered_set_of</span></code>
 144                   </p>
 145                 </td>
 146 <td>
 147                   <p>
 148                     <span class="emphasis"><em>constant</em></span>
 149                   </p>
 150                 </td>
 151 </tr>
 152 <tr>
 153 <td>
 154                   <p>
 155                     <code class="computeroutput"><span class="identifier">unordered_multiset_of</span></code>
 156                   </p>
 157                 </td>
 158 <td>
 159                   <p>
 160                     <span class="emphasis"><em>constant</em></span>
 161                   </p>
 162                 </td>
 163 </tr>
 164 <tr>
 165 <td>
 166                   <p>
 167                     <code class="computeroutput"><span class="identifier">list_of</span></code>
 168                   </p>
 169                 </td>
 170 <td>
 171                   <p>
 172                     <span class="emphasis"><em>mutable</em></span>
 173                   </p>
 174                 </td>
 175 </tr>
 176 <tr>
 177 <td>
 178                   <p>
 179                     <code class="computeroutput"><span class="identifier">vector_of</span></code>
 180                   </p>
 181                 </td>
 182 <td>
 183                   <p>
 184                     <span class="emphasis"><em>mutable</em></span>
 185                   </p>
 186                 </td>
 187 </tr>
 188 <tr>
 189 <td>
 190                   <p>
 191                     <code class="computeroutput"><span class="identifier">unconstrained_set_of</span></code>
 192                   </p>
 193                 </td>
 194 <td>
 195                   <p>
 196                     <span class="emphasis"><em>mutable</em></span>
 197                   </p>
 198                 </td>
 199 </tr>
 200 </tbody>
 201 </table></div>
 202 <p>
 203           Here are some examples. When dereferenced the iterators returns a type
 204           that is <span class="emphasis"><em>signature-compatible</em></span> with these types.
 205         </p>
 206 <div class="informaltable"><table class="table">
 207 <colgroup>
 208 <col>
 209 <col>
 210 </colgroup>
 211 <thead><tr>
 212 <th>
 213                   <p>
 214                     Bimap type
 215                   </p>
 216                 </th>
 217 <th>
 218                   <p>
 219                     Signature-compatible types
 220                   </p>
 221                 </th>
 222 </tr></thead>
 223 <tbody>
 224 <tr>
 225 <td>
 226                   <p>
 227                     <code class="computeroutput"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span><span class="identifier">B</span><span class="special">&gt;</span></code>
 228                   </p>
 229                 </td>
 230 <td>
 231                   <p>
 232                     <code class="computeroutput"><span class="identifier">iterator</span> </code> <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">relation</span><span class="special">&lt;</span><span class="keyword">const</span>
 233                     <span class="identifier">A</span><span class="special">,</span><span class="keyword">const</span> <span class="identifier">B</span><span class="special">&gt;</span></code>
 234                   </p>
 235                   <p>
 236                     <code class="computeroutput"><span class="identifier">left_iterator</span> </code>
 237                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">const</span>
 238                     <span class="identifier">A</span><span class="special">,</span><span class="keyword">const</span> <span class="identifier">B</span><span class="special">&gt;</span></code>
 239                   </p>
 240                   <p>
 241                     <code class="computeroutput"><span class="identifier">right_iterator</span></code>
 242                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">const</span>
 243                     <span class="identifier">B</span><span class="special">,</span><span class="keyword">const</span> <span class="identifier">A</span><span class="special">&gt;</span></code>
 244                   </p>
 245                 </td>
 246 </tr>
 247 <tr>
 248 <td>
 249                   <p>
 250                     <code class="computeroutput"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="identifier">multiset_of</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">&gt;,</span><span class="identifier">unordered_set_of</span><span class="special">&lt;</span><span class="identifier">B</span><span class="special">&gt;</span>
 251                     <span class="special">&gt;</span></code>
 252                   </p>
 253                 </td>
 254 <td>
 255                   <p>
 256                     <code class="computeroutput"><span class="identifier">iterator</span> </code> <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">relation</span><span class="special">&lt;</span><span class="keyword">const</span>
 257                     <span class="identifier">A</span><span class="special">,</span><span class="keyword">const</span> <span class="identifier">B</span><span class="special">&gt;</span></code>
 258                   </p>
 259                   <p>
 260                     <code class="computeroutput"><span class="identifier">left_iterator</span> </code>
 261                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">const</span>
 262                     <span class="identifier">A</span><span class="special">,</span><span class="keyword">const</span> <span class="identifier">B</span><span class="special">&gt;</span></code>
 263                   </p>
 264                   <p>
 265                     <code class="computeroutput"><span class="identifier">right_iterator</span></code>
 266                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">const</span>
 267                     <span class="identifier">B</span><span class="special">,</span><span class="keyword">const</span> <span class="identifier">A</span><span class="special">&gt;</span></code>
 268                   </p>
 269                 </td>
 270 </tr>
 271 <tr>
 272 <td>
 273                   <p>
 274                     <code class="computeroutput"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="identifier">set_of</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">&gt;,</span><span class="identifier">list_of</span><span class="special">&lt;</span><span class="identifier">B</span><span class="special">&gt;</span>
 275                     <span class="special">&gt;</span></code>
 276                   </p>
 277                 </td>
 278 <td>
 279                   <p>
 280                     <code class="computeroutput"><span class="identifier">iterator</span> </code> <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">relation</span><span class="special">&lt;</span><span class="keyword">const</span>
 281                     <span class="identifier">A</span><span class="special">,</span><span class="identifier">B</span><span class="special">&gt;</span></code>
 282                   </p>
 283                   <p>
 284                     <code class="computeroutput"><span class="identifier">left_iterator</span> </code>
 285                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">const</span>
 286                     <span class="identifier">A</span><span class="special">,</span><span class="identifier">B</span><span class="special">&gt;</span></code>
 287                   </p>
 288                   <p>
 289                     <code class="computeroutput"><span class="identifier">right_iterator</span></code>
 290                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">B</span><span class="special">,</span><span class="keyword">const</span>
 291                     <span class="identifier">A</span><span class="special">&gt;</span></code>
 292                   </p>
 293                 </td>
 294 </tr>
 295 <tr>
 296 <td>
 297                   <p>
 298                     <code class="computeroutput"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="identifier">vector_of</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">&gt;,</span><span class="identifier">set_of</span><span class="special">&lt;</span><span class="identifier">B</span><span class="special">&gt;</span>
 299                     <span class="special">&gt;</span></code>
 300                   </p>
 301                 </td>
 302 <td>
 303                   <p>
 304                     <code class="computeroutput"><span class="identifier">iterator</span> </code> <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">relation</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span><span class="keyword">const</span>
 305                     <span class="identifier">B</span><span class="special">&gt;</span></code>
 306                   </p>
 307                   <p>
 308                     <code class="computeroutput"><span class="identifier">left_iterator</span> </code>
 309                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span><span class="keyword">const</span>
 310                     <span class="identifier">B</span><span class="special">&gt;</span></code>
 311                   </p>
 312                   <p>
 313                     <code class="computeroutput"><span class="identifier">right_iterator</span></code>
 314                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">const</span>
 315                     <span class="identifier">B</span><span class="special">,</span><span class="identifier">A</span><span class="special">&gt;</span></code>
 316                   </p>
 317                 </td>
 318 </tr>
 319 <tr>
 320 <td>
 321                   <p>
 322                     <code class="computeroutput"><span class="identifier">bimap</span><span class="special">&lt;</span><span class="identifier">list_of</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">&gt;,</span><span class="identifier">unconstrained_set_of</span><span class="special">&lt;</span><span class="identifier">B</span><span class="special">&gt;</span>
 323                     <span class="special">&gt;</span></code>
 324                   </p>
 325                 </td>
 326 <td>
 327                   <p>
 328                     <code class="computeroutput"><span class="identifier">iterator</span> </code> <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">relation</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span><span class="identifier">B</span><span class="special">&gt;</span></code>
 329                   </p>
 330                   <p>
 331                     <code class="computeroutput"><span class="identifier">left_iterator</span> </code>
 332                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">,</span><span class="identifier">B</span><span class="special">&gt;</span></code>
 333                   </p>
 334                   <p>
 335                     <code class="computeroutput"><span class="identifier">right_iterator</span></code>
 336                     <span class="bold"><strong>-&gt;</strong></span> <code class="computeroutput"><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">B</span><span class="special">,</span><span class="identifier">A</span><span class="special">&gt;</span></code>
 337                   </p>
 338                 </td>
 339 </tr>
 340 </tbody>
 341 </table></div>
 342 </div>
 343 <div class="section boost_bimap_the_tutorial_differences_with_standard_maps_operator_____and_at__">
 344 <div class="titlepage"><div><div><h4 class="title">
 345 <a name="boost_bimap.the_tutorial.differences_with_standard_maps.operator_____and_at__"></a><a class="link" href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.operator_____and_at__" title="operator[] and at()">operator[]
 346         and at()</a>
 347 </h4></div></div></div>
 348 <p>
 349           <code class="computeroutput"><span class="identifier">set_of</span></code> and <code class="computeroutput"><span class="identifier">unordered_set_of</span></code> map views overload
 350           <code class="computeroutput"><span class="keyword">operator</span><span class="special">[]</span></code>
 351           to retrieve the associated data of a given key only when the other collection
 352           type is a mutable one. In these cases it works in the same way as the standard.
 353         </p>
 354 <pre class="programlisting"><span class="identifier">bimap</span><span class="special">&lt;</span> <span class="identifier">unorderd_set_of</span><span class="special">&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;,</span> <span class="identifier">list_of</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">bm</span><span class="special">;</span>
 355
 356 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">[</span><span class="string">"one"</span><span class="special">]</span> <span class="special">=</span> <span class="number">1</span><span class="special">;</span> <span class="comment">// Ok</span>
 357 </pre>
 358 <p>
 359           The standard defines an access function for <code class="computeroutput"><span class="identifier">map</span></code>
 360           and <code class="computeroutput"><span class="identifier">unordered_map</span></code>:
 361         </p>
 362 <pre class="programlisting"><span class="keyword">const</span> <span class="identifier">data_type</span> <span class="special">&amp;</span> <span class="identifier">at</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">key_type</span> <span class="special">&amp;</span> <span class="identifier">k</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
 363       <span class="identifier">data_type</span> <span class="special">&amp;</span> <span class="identifier">at</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">key_type</span> <span class="special">&amp;</span> <span class="identifier">k</span><span class="special">);</span>
 364 </pre>
 365 <p>
 366           These functions look for a key and returns the associated data value, but
 367           throws a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">out_of_range</span></code> exception if the key is
 368           not found.
 369         </p>
 370 <p>
 371           In bimaps the constant version of these functions is given for <code class="computeroutput"><span class="identifier">set_of</span></code> and <code class="computeroutput"><span class="identifier">unorderd_set_of</span></code>
 372           map views independently of the other collection type. The mutable version
 373           is only provided when the other collection type is mutable.
 374         </p>
 375 <p>
 376           The following examples shows the behaviour of <code class="computeroutput"><span class="identifier">at</span><span class="special">(</span><span class="identifier">key</span><span class="special">)</span></code>
 377         </p>
 378 <p>
 379           <a href="../../../../example/at_function_examples.cpp" target="_top">Go to source code</a>
 380         </p>
 381 <p>
 382 </p>
 383 <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special">&lt;</span> <span class="identifier">set_of</span><span class="special">&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">&gt;,</span> <span class="identifier">list_of</span><span class="special">&lt;</span> <span class="keyword">int</span> <span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">bm_type</span><span class="special">;</span>
 384 <span class="identifier">bm_type</span> <span class="identifier">bm</span><span class="special">;</span>
 385
 386 <span class="keyword">try</span>
 387 <span class="special">{</span>
 388     <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">.</span><span class="identifier">at</span><span class="special">(</span><span class="string">"one"</span><span class="special">)</span> <span class="special">=</span> <span class="number">1</span><span class="special">;</span> <span class="comment">// throws std::out_of_range</span>
 389 <span class="special">}</span>
 390 <span class="keyword">catch</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">out_of_range</span> <span class="special">&amp;</span> <span class="identifier">e</span> <span class="special">)</span> <span class="special">{}</span>
 391
 392 <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">empty</span><span class="special">()</span> <span class="special">);</span>
 393
 394 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">[</span><span class="string">"one"</span><span class="special">]</span> <span class="special">=</span> <span class="number">1</span><span class="special">;</span> <span class="comment">// Ok</span>
 395
 396 <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span><span class="special">.</span><span class="identifier">at</span><span class="special">(</span><span class="string">"one"</span><span class="special">)</span> <span class="special">==</span> <span class="number">1</span> <span class="special">);</span> <span class="comment">// Ok</span>
 397 </pre>
 398 <p>
 399         </p>
 400 <p>
 401 </p>
 402 <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special">&lt;</span> <span class="identifier">multiset_of</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;,</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="special">&gt;</span> <span class="identifier">bm_type</span><span class="special">;</span>
 403 <span class="identifier">bm_type</span> <span class="identifier">bm</span><span class="special">;</span>
 404
 405 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">right</span><span class="special">[</span><span class="number">1</span><span class="special">]</span> <span class="special">=</span> <span class="string">"one"</span><span class="special">;</span> <span class="comment">// compilation error</span>
 406
 407 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">right_value_type</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="string">"one"</span><span class="special">)</span> <span class="special">);</span>
 408
 409 <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">at</span><span class="special">(</span><span class="number">1</span><span class="special">)</span> <span class="special">==</span> <span class="string">"one"</span> <span class="special">);</span> <span class="comment">// Ok</span>
 410
 411 <span class="keyword">try</span>
 412 <span class="special">{</span>
 413     <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">at</span><span class="special">(</span><span class="number">2</span><span class="special">);</span> <span class="comment">// throws std::out_of_range</span>
 414 <span class="special">}</span>
 415 <span class="keyword">catch</span><span class="special">(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">out_of_range</span> <span class="special">&amp;</span> <span class="identifier">e</span> <span class="special">)</span> <span class="special">{}</span>
 416
 417 <span class="identifier">bm</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">at</span><span class="special">(</span><span class="number">1</span><span class="special">)</span> <span class="special">=</span> <span class="string">"1"</span><span class="special">;</span> <span class="comment">// compilation error</span>
 418 </pre>
 419 <p>
 420         </p>
 421 </div>
 422 <div class="section boost_bimap_the_tutorial_differences_with_standard_maps_complexity_of_operations">
 423 <div class="titlepage"><div><div><h4 class="title">
 424 <a name="boost_bimap.the_tutorial.differences_with_standard_maps.complexity_of_operations"></a><a class="link" href="differences_with_standard_maps.html#boost_bimap.the_tutorial.differences_with_standard_maps.complexity_of_operations" title="Complexity of operations">Complexity
 425         of operations</a>
 426 </h4></div></div></div>
 427 <p>
 428           The complexity of some operations is different in bimaps. Read <a class="link" href="../reference/bimap_reference.html#complexity_signature_explanation">the
 429           reference</a> to find the complexity of each function.
 430         </p>
 431 </div>
 432 </div>
 433 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 434 <td align="left"></td>
 435 <td align="right"><div class="copyright-footer">Copyright &#169; 2006-2012 Matias Capeletto<p>
 436         Distributed under the Boost Software License, Version 1.0. (See accompanying
 437         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>)
 438       </p>
 439 </div></td>
 440 </tr></table>
 441 <hr>
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