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- <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 class="toc">
- <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="boost_bimap.the_tutorial.controlling_collection_types.freedom_of_choice.t0"></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" style="list-style-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>
- <h6>
- <a name="boost_bimap.the_tutorial.controlling_collection_types.examples.h0"></a>
- <span class="phrase"><a name="boost_bimap.the_tutorial.controlling_collection_types.examples.countries_populations"></a></span><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 requirements are:
- </p>
- <div class="orderedlist"><ol class="orderedlist" type="1">
- <li class="listitem">
- Get a list of countries in decreasing order of their populations.
- </li>
- <li class="listitem">
- Given a country, get their population.
- </li>
- </ol></div>
- <p>
- Lets create the appropriate 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_bimap.the_tutorial.controlling_collection_types.examples.c0" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples.c1"><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_bimap.the_tutorial.controlling_collection_types.examples.c2" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples.c3"><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>
- <div class="calloutlist"><table border="0" summary="Callout list">
- <tr>
- <td width="5%" valign="top" align="left"><p><a name="boost_bimap.the_tutorial.controlling_collection_types.examples.c1"></a><a href="#boost_bimap.the_tutorial.controlling_collection_types.examples.c0"><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_bimap.the_tutorial.controlling_collection_types.examples.c3"></a><a href="#boost_bimap.the_tutorial.controlling_collection_types.examples.c2"><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>
- <h6>
- <a name="boost_bimap.the_tutorial.controlling_collection_types.examples.h1"></a>
- <span class="phrase"><a name="boost_bimap.the_tutorial.controlling_collection_types.examples.repetitions_counter"></a></span><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_bimap.the_tutorial.controlling_collection_types.examples.c4" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples.c5"><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_bimap.the_tutorial.controlling_collection_types.examples.c6" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples.c7"><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_bimap.the_tutorial.controlling_collection_types.examples.c8" href="controlling_collection_types.html#boost_bimap.the_tutorial.controlling_collection_types.examples.c9"><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>
- <div class="calloutlist"><table border="0" summary="Callout list">
- <tr>
- <td width="5%" valign="top" align="left"><p><a name="boost_bimap.the_tutorial.controlling_collection_types.examples.c5"></a><a href="#boost_bimap.the_tutorial.controlling_collection_types.examples.c4"><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_bimap.the_tutorial.controlling_collection_types.examples.c7"></a><a href="#boost_bimap.the_tutorial.controlling_collection_types.examples.c6"><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_bimap.the_tutorial.controlling_collection_types.examples.c9"></a><a href="#boost_bimap.the_tutorial.controlling_collection_types.examples.c8"><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>
- </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 © 2006-2012 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>
- <div class="spirit-nav">
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