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| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_bimap.the_tutorial.controlling_collection_types"></a><a class="link" href="controlling_collection_types.html" title="Controlling collection types">Controlling |
| collection types</a> |
| </h3></div></div></div> |
| <div class="toc"><dl> |
| <dt><span class="section"><a href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.freedom_of_choice">Freedom |
| of choice</a></span></dt> |
| <dt><span class="section"><a href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.configuration_parameters">Configuration |
| parameters</a></span></dt> |
| <dt><span class="section"><a href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples">Examples</a></span></dt> |
| </dl></div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="boost_bimap.the_tutorial.controlling_collection_types.freedom_of_choice"></a><a class="link" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.freedom_of_choice" title="Freedom of choice">Freedom |
| of choice</a> |
| </h4></div></div></div> |
| <p> |
| As has already been said, in STL maps, you can only control the constraints |
| from one of the collections, namely the one that you are viewing. In Boost.Bimap, |
| you can control both and it is as easy as using the STL. |
| </p> |
| <p> |
| <span class="inlinemediaobject"><img src="../../images/bimap/extended.mapping.framework.png" alt="extended.mapping.framework"></span> |
| </p> |
| <p> |
| The idea is to use the same constraint names that are used in the standard. |
| If you don't specify the collection type, Boost.Bimap assumes that the |
| collection is a set. The instantiation of a bimap with custom collection |
| types looks like this: |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special"><</span> <span class="bold"><strong>CollectionType</strong></span><span class="identifier">_of</span><span class="special"><</span><span class="identifier">A</span><span class="special">>,</span> <span class="bold"><strong>CollectionType</strong></span><span class="identifier">_of</span><span class="special"><</span><span class="identifier">B</span><span class="special">></span> <span class="special">></span> <span class="identifier">bm_type</span><span class="special">;</span> |
| </pre> |
| <p> |
| The following is the list of all supported collection types. |
| </p> |
| <div class="table"> |
| <a name="id767190"></a><p class="title"><b>Table 1.2. Collection of Key Types</b></p> |
| <div class="table-contents"><table class="table" summary="Collection of Key Types"> |
| <colgroup> |
| <col> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| name |
| </p> |
| </th> |
| <th> |
| <p> |
| Features |
| </p> |
| </th> |
| <th> |
| <p> |
| map view type |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">set_of</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>ordered, unique</em></span> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">map</span></code> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">multiset_of</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>ordered </em></span> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">multimap</span></code> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">unordered_set_of</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>hashed, unique </em></span> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">unordered_map</span></code> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">unordered_multiset_of</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>hashed </em></span> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">unordered_multimap</span></code> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">list_of</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>sequenced </em></span> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">list_map</span></code> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">vector_of</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>random access </em></span> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">vector_map</span></code> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">unconstrained_set_of</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>unconstrained </em></span> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="emphasis"><em>can not be viewed</em></span> |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <br class="table-break"><p> |
| <code class="computeroutput"><span class="identifier">list_of</span></code> and <code class="computeroutput"><span class="identifier">vector_of</span></code> map views are not associated |
| with any existing STL associative containers. They are two examples of |
| unsorted associative containers. <code class="computeroutput"><span class="identifier">unconstrained_set_of</span></code> |
| allow the user to ignore a view. This will be explained later. |
| </p> |
| <p> |
| <span class="inlinemediaobject"><img src="../../images/bimap/bimap.structures.png" alt="bimap.structures"></span> |
| </p> |
| <p> |
| The selection of the collection type affects the possible operations that |
| you can perform with each side of the bimap and the time it takes to do |
| each. If we have: |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special"><</span> <span class="bold"><strong>CollectionType</strong></span><span class="identifier">_of</span><span class="special"><</span><span class="identifier">A</span><span class="special">>,</span> <span class="bold"><strong>CollectionType</strong></span><span class="identifier">_of</span><span class="special"><</span><span class="identifier">B</span><span class="special">></span> <span class="special">></span> <span class="identifier">bm_type</span><span class="special">;</span> |
| <span class="identifier">bm_type</span> <span class="identifier">bm</span><span class="special">;</span> |
| </pre> |
| <p> |
| The following now describes the resulting map views of the bidirectional |
| map. |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <code class="computeroutput"><span class="identifier">bm</span><span class="special">.</span><span class="identifier">left</span></code> is signature-compatible with |
| <span class="bold"><strong>LeftMapType</strong></span><code class="computeroutput"><span class="special"><</span><span class="identifier">A</span><span class="special">,</span><span class="identifier">B</span><span class="special">></span></code> |
| </li> |
| <li class="listitem"> |
| <code class="computeroutput"><span class="identifier">bm</span><span class="special">.</span><span class="identifier">right</span></code> is signature-compatible with |
| <span class="bold"><strong>RightMapType</strong></span><code class="computeroutput"><span class="special"><</span><span class="identifier">B</span><span class="special">,</span><span class="identifier">A</span><span class="special">></span></code> |
| </li> |
| </ul></div> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="boost_bimap.the_tutorial.controlling_collection_types.configuration_parameters"></a><a class="link" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.configuration_parameters" title="Configuration parameters">Configuration |
| parameters</a> |
| </h4></div></div></div> |
| <p> |
| Each collection type template has different parameters to control its behaviour. |
| For example, in <code class="computeroutput"><span class="identifier">set_of</span></code> |
| specification, you can pass a Functor type that compares two types. All |
| of these parameters are exactly the same as those of the standard library |
| container, except for the allocator type. You will learn later how to change |
| the allocator for a bimap. |
| </p> |
| <p> |
| The following table lists the meanings of each collection type's parameters. |
| </p> |
| <div class="informaltable"><table class="table"> |
| <colgroup> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| name |
| </p> |
| </th> |
| <th> |
| <p> |
| Additional Parameters |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">set_of</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">KeyComp</span><span class="special">></span></code> |
| </p> |
| <p> |
| <code class="computeroutput"><span class="identifier">multiset_of</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">KeyComp</span><span class="special">></span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="bold"><strong>KeyComp </strong></span> is a Functor that compares |
| two types using a less-than operator. By default, this is <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">unordered_set_of</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">HashFunctor</span><span class="special">,</span><span class="identifier">EqualKey</span><span class="special">></span></code> |
| </p> |
| <p> |
| <code class="computeroutput"><span class="identifier">unordered_multiset_of</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">HashFunctor</span><span class="special">,</span><span class="identifier">EqualKey</span><span class="special">></span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <span class="bold"><strong>HashFunctor </strong></span> converts a <code class="computeroutput"><span class="identifier">T</span></code> object 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 |
| is <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">hash</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code>. |
| </p> |
| <p> |
| <span class="bold"><strong>EqualKey </strong></span> is a Functor that |
| tests two types for equality. By default, the equality operator |
| is <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">equal_to</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">list_of</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| No additional parameters. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">vector_of</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| No additional parameters. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">unconstrained_set_of</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| No additional parameters. |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="boost_bimap.the_tutorial.controlling_collection_types.examples"></a><a class="link" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples" title="Examples">Examples</a> |
| </h4></div></div></div> |
| <a name="boost_bimap.the_tutorial.controlling_collection_types.examples.countries_populations"></a><h6> |
| <a name="id768285"></a> |
| <a class="link" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples.countries_populations">Countries |
| Populations</a> |
| </h6> |
| <p> |
| We want to store countries populations. The requeriments are: |
| </p> |
| <div class="orderedlist"><ol class="orderedlist" type="1"> |
| <li class="listitem"> |
| Get a list of countries in decresing order of their populations. |
| </li> |
| <li class="listitem"> |
| Given a countrie, get their population. |
| </li> |
| </ol></div> |
| <p> |
| Lets create the appropiate bimap. |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special"><</span> |
| |
| <span class="identifier">unordered_set_of</span><span class="special"><</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">>,</span> |
| <span class="identifier">multiset_of</span><span class="special"><</span> <span class="keyword">long</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">greater</span><span class="special"><</span><span class="keyword">long</span><span class="special">></span> <span class="special">></span> |
| |
| <span class="special">></span> <span class="identifier">populations_bimap</span><span class="special">;</span> |
| </pre> |
| <p> |
| First of all countries names are unique identifiers, while two countries |
| may have the same population. This is why we choose <span class="bold"><strong>multi</strong></span><code class="computeroutput"><span class="identifier">set_of</span></code> for populations. |
| </p> |
| <p> |
| Using a <code class="computeroutput"><span class="identifier">multiset_of</span></code> for |
| population allow us to iterate over the data. Since listing countries ordered |
| by their names is not a requisite, we can use an <code class="computeroutput"><span class="identifier">unordered_set_of</span></code> |
| that allows constant order look up. |
| </p> |
| <p> |
| And now lets use it in a complete example |
| </p> |
| <p> |
| <a href="../../../../example/population_bimap.cpp" target="_top">Go to source code</a> |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special"><</span> |
| |
| <span class="identifier">unordered_set_of</span><span class="special"><</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">>,</span> |
| <span class="identifier">multiset_of</span><span class="special"><</span> <span class="keyword">long</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">greater</span><span class="special"><</span><span class="keyword">long</span><span class="special">></span> <span class="special">></span> |
| |
| <span class="special">></span> <span class="identifier">population_bimap</span><span class="special">;</span> |
| |
| <span class="keyword">typedef</span> <span class="identifier">population_bimap</span><span class="special">::</span><span class="identifier">value_type</span> <span class="identifier">population</span><span class="special">;</span> |
| |
| <span class="identifier">population_bimap</span> <span class="identifier">pop</span><span class="special">;</span> |
| <span class="identifier">pop</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">population</span><span class="special">(</span><span class="string">"China"</span><span class="special">,</span> <span class="number">1321000000</span><span class="special">)</span> <span class="special">);</span> |
| <span class="identifier">pop</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">population</span><span class="special">(</span><span class="string">"India"</span><span class="special">,</span> <span class="number">1129000000</span><span class="special">)</span> <span class="special">);</span> |
| <span class="identifier">pop</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">population</span><span class="special">(</span><span class="string">"United States"</span><span class="special">,</span> <span class="number">301950000</span><span class="special">)</span> <span class="special">);</span> |
| <span class="identifier">pop</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">population</span><span class="special">(</span><span class="string">"Indonesia"</span><span class="special">,</span> <span class="number">234950000</span><span class="special">)</span> <span class="special">);</span> |
| <span class="identifier">pop</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">population</span><span class="special">(</span><span class="string">"Brazil"</span><span class="special">,</span> <span class="number">186500000</span><span class="special">)</span> <span class="special">);</span> |
| <span class="identifier">pop</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span> <span class="identifier">population</span><span class="special">(</span><span class="string">"Pakistan"</span><span class="special">,</span> <span class="number">163630000</span><span class="special">)</span> <span class="special">);</span> |
| |
| <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Countries by their population:"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> |
| |
| <span class="comment">// First requirement |
| </span><a class="co" name="boost_bimap4co" href="controlling_collection_types.html#boost_bimap4"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a><span class="keyword">for</span><span class="special">(</span> <span class="identifier">population_bimap</span><span class="special">::</span><span class="identifier">right_const_iterator</span> |
| <span class="identifier">i</span> <span class="special">=</span> <span class="identifier">pop</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">iend</span> <span class="special">=</span> <span class="identifier">pop</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">end</span><span class="special">();</span> |
| <span class="identifier">i</span> <span class="special">!=</span> <span class="identifier">iend</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">i</span> <span class="special">)</span> |
| <span class="special">{</span> |
| <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">i</span><span class="special">-></span><span class="identifier">second</span> <span class="special"><<</span> <span class="string">" with "</span> <span class="special"><<</span> <span class="identifier">i</span><span class="special">-></span><span class="identifier">first</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> |
| <span class="special">}</span> |
| |
| <span class="comment">// Second requirement |
| </span><a class="co" name="boost_bimap5co" href="controlling_collection_types.html#boost_bimap5"><img src="../../../../../../doc/src/images/callouts/2.png" alt="2" border="0"></a><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Population of China: "</span> <span class="special"><<</span> <span class="identifier">pop</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">"China"</span><span class="special">)</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> |
| </pre> |
| <p> |
| </p> |
| <p> |
| </p> |
| <div class="calloutlist"><table border="0" summary="Callout list"> |
| <tr> |
| <td width="5%" valign="top" align="left"><p><a name="boost_bimap4"></a><a href="#boost_bimap4co"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a> </p></td> |
| <td valign="top" align="left"><p> The right map view works like a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">multimap</span><span class="special"><</span> <span class="keyword">long</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">greater</span><span class="special"><</span><span class="keyword">long</span><span class="special">></span> <span class="special">></span></code>, |
| We can iterate over it to print the results in the required order. </p></td> |
| </tr> |
| <tr> |
| <td width="5%" valign="top" align="left"><p><a name="boost_bimap5"></a><a href="#boost_bimap5co"><img src="../../../../../../doc/src/images/callouts/2.png" alt="2" border="0"></a> </p></td> |
| <td valign="top" align="left"><p> The |
| left map view works like a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">unordered_map</span><span class="special"><</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">,</span> <span class="keyword">long</span> <span class="special">></span></code>, given the name of the country we can |
| use it to search for the population in constant time </p></td> |
| </tr> |
| </table></div> |
| <p> |
| </p> |
| <a name="boost_bimap.the_tutorial.controlling_collection_types.examples.repetitions_counter"></a><h6> |
| <a name="id769726"></a> |
| <a class="link" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples.repetitions_counter">Repetitions |
| counter</a> |
| </h6> |
| <p> |
| We want to count the repetitions for each word in a text and print them |
| in order of appearance. |
| </p> |
| <p> |
| <a href="../../../../example/repetitions_counter.cpp" target="_top">Go to source code</a> |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span> |
| <span class="special"><</span> |
| <span class="identifier">unordered_set_of</span><span class="special"><</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">>,</span> |
| <span class="identifier">list_of</span><span class="special"><</span> <span class="identifier">counter</span> <span class="special">></span> <a class="co" name="boost_bimap6co" href="controlling_collection_types.html#boost_bimap6"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a> |
| |
| <span class="special">></span> <span class="identifier">word_counter</span><span class="special">;</span> |
| |
| <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">tokenizer</span><span class="special"><</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">char_separator</span><span class="special"><</span><span class="keyword">char</span><span class="special">></span> <span class="special">></span> <span class="identifier">text_tokenizer</span><span class="special">;</span> |
| |
| <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">text</span><span class="special">=</span> |
| <span class="string">"Relations between data in the STL are represented with maps."</span> |
| <span class="string">"A map is a directed relation, by using it you are representing "</span> |
| <span class="string">"a mapping. In this directed relation, the first type is related to "</span> |
| <span class="string">"the second type but it is not true that the inverse relationship "</span> |
| <span class="string">"holds. This is useful in a lot of situations, but there are some "</span> |
| <span class="string">"relationships that are bidirectional by nature."</span><span class="special">;</span> |
| |
| <span class="comment">// feed the text into the container |
| </span><span class="identifier">word_counter</span> <span class="identifier">wc</span><span class="special">;</span> |
| <span class="identifier">text_tokenizer</span> <span class="identifier">tok</span><span class="special">(</span><span class="identifier">text</span><span class="special">,</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">char_separator</span><span class="special"><</span><span class="keyword">char</span><span class="special">>(</span><span class="string">" \t\n.,;:!?'\"-"</span><span class="special">));</span> |
| |
| <span class="keyword">for</span><span class="special">(</span> <span class="identifier">text_tokenizer</span><span class="special">::</span><span class="identifier">const_iterator</span> <span class="identifier">it</span> <span class="special">=</span> <span class="identifier">tok</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">it_end</span> <span class="special">=</span> <span class="identifier">tok</span><span class="special">.</span><span class="identifier">end</span><span class="special">();</span> |
| <span class="identifier">it</span> <span class="special">!=</span> <span class="identifier">it_end</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">it</span> <span class="special">)</span> |
| <span class="special">{</span> |
| <a class="co" name="boost_bimap7co" href="controlling_collection_types.html#boost_bimap7"><img src="../../../../../../doc/src/images/callouts/2.png" alt="2" border="0"></a><span class="special">++</span> <span class="identifier">wc</span><span class="special">.</span><span class="identifier">left</span><span class="special">[*</span><span class="identifier">it</span><span class="special">];</span> |
| <span class="special">}</span> |
| |
| <span class="comment">// list words with counters by order of appearance |
| </span><a class="co" name="boost_bimap8co" href="controlling_collection_types.html#boost_bimap8"><img src="../../../../../../doc/src/images/callouts/3.png" alt="3" border="0"></a><span class="keyword">for</span><span class="special">(</span> <span class="identifier">word_counter</span><span class="special">::</span><span class="identifier">right_const_iterator</span> |
| <span class="identifier">wit</span> <span class="special">=</span> <span class="identifier">wc</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">wit_end</span> <span class="special">=</span> <span class="identifier">wc</span><span class="special">.</span><span class="identifier">right</span><span class="special">.</span><span class="identifier">end</span><span class="special">();</span> |
| |
| <span class="identifier">wit</span> <span class="special">!=</span> <span class="identifier">wit_end</span><span class="special">;</span> <span class="special">++</span><span class="identifier">wit</span> <span class="special">)</span> |
| <span class="special">{</span> |
| <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">wit</span><span class="special">-></span><span class="identifier">second</span> <span class="special"><<</span> <span class="string">": "</span> <span class="special"><<</span> <span class="identifier">wit</span><span class="special">-></span><span class="identifier">first</span><span class="special">;</span> |
| <span class="special">}</span> |
| </pre> |
| <p> |
| </p> |
| <p> |
| </p> |
| <div class="calloutlist"><table border="0" summary="Callout list"> |
| <tr> |
| <td width="5%" valign="top" align="left"><p><a name="boost_bimap6"></a><a href="#boost_bimap6co"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a> </p></td> |
| <td valign="top" align="left"><p> <code class="computeroutput"><span class="identifier">counter</span></code> is an integer that |
| is initialized in zero in the constructor </p></td> |
| </tr> |
| <tr> |
| <td width="5%" valign="top" align="left"><p><a name="boost_bimap7"></a><a href="#boost_bimap7co"><img src="../../../../../../doc/src/images/callouts/2.png" alt="2" border="0"></a> </p></td> |
| <td valign="top" align="left"><p> Because the right collection |
| type is <code class="computeroutput"><span class="identifier">list_of</span></code>, the right |
| data is not used a key and can be modified in the same way as with standard |
| maps. </p></td> |
| </tr> |
| <tr> |
| <td width="5%" valign="top" align="left"><p><a name="boost_bimap8"></a><a href="#boost_bimap8co"><img src="../../../../../../doc/src/images/callouts/3.png" alt="3" border="0"></a> </p></td> |
| <td valign="top" align="left"><p> When we insert the elements using the left map view, the element |
| is inserted at the end of the list. </p></td> |
| </tr> |
| </table></div> |
| <p> |
| </p> |
| </div> |
| </div> |
| <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> |
| <td align="left"></td> |
| <td align="right"><div class="copyright-footer">Copyright © 2006 -2007 Matias Capeletto<p> |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 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>) |
| </p> |
| </div></td> |
| </tr></table> |
| <hr> |
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