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| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_bimap.the_tutorial.useful_functions"></a><a class="link" href="useful_functions.html" title="Useful functions">Useful functions</a> |
| </h3></div></div></div> |
| <div class="toc"><dl> |
| <dt><span class="section"><a href="useful_functions.html#boost_bimap.the_tutorial.useful_functions.projection_of_iterators">Projection |
| of iterators</a></span></dt> |
| <dt><span class="section"><a href="useful_functions.html#boost_bimap.the_tutorial.useful_functions.replace_and_modify">replace |
| and modify</a></span></dt> |
| <dt><span class="section"><a href="useful_functions.html#boost_bimap.the_tutorial.useful_functions.retrieval_of_ranges">Retrieval |
| of ranges</a></span></dt> |
| </dl></div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="boost_bimap.the_tutorial.useful_functions.projection_of_iterators"></a><a class="link" href="useful_functions.html#boost_bimap.the_tutorial.useful_functions.projection_of_iterators" title="Projection of iterators">Projection |
| of iterators</a> |
| </h4></div></div></div> |
| <p> |
| Iterators can be projected to any of the three views of the bimap. A bimap |
| provides three member functions to cope with projection: <code class="computeroutput"><span class="identifier">project_left</span></code>, <code class="computeroutput"><span class="identifier">project_right</span></code> |
| and <code class="computeroutput"><span class="identifier">project_up</span></code>, with projects |
| iterators to the <span class="emphasis"><em>left map view</em></span>, the <span class="emphasis"><em>right |
| map view</em></span> and the <span class="emphasis"><em>collection of relations view</em></span>. |
| These functions take any iterator from the bimap and retrieve an iterator |
| over the projected view pointing to the same element. |
| </p> |
| <p> |
| Here is an example that uses projection: |
| </p> |
| <p> |
| <a href="../../../../example/projection.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">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">int</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">int</span><span class="special">></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> |
| <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">value_type</span><span class="special">(</span><span class="string">"John"</span> <span class="special">,</span><span class="number">34</span><span class="special">)</span> <span class="special">);</span> |
| <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">value_type</span><span class="special">(</span><span class="string">"Peter"</span><span class="special">,</span><span class="number">24</span><span class="special">)</span> <span class="special">);</span> |
| <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">value_type</span><span class="special">(</span><span class="string">"Mary"</span> <span class="special">,</span><span class="number">12</span><span class="special">)</span> <span class="special">);</span> |
| |
| <span class="comment">// Find the name of the next younger person after Peter |
| </span> |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_const_iterator</span> <span class="identifier">name_iter</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">find</span><span class="special">(</span><span class="string">"Peter"</span><span class="special">);</span> |
| |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">right_const_iterator</span> <span class="identifier">years_iter</span> <span class="special">=</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">project_right</span><span class="special">(</span><span class="identifier">name_iter</span><span class="special">);</span> |
| |
| <span class="special">++</span><span class="identifier">years_iter</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">"The next younger person after Peter is "</span> <span class="special"><<</span> <span class="identifier">years_iter</span><span class="special">-></span><span class="identifier">second</span><span class="special">;</span> |
| </pre> |
| <p> |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="boost_bimap.the_tutorial.useful_functions.replace_and_modify"></a><a class="link" href="useful_functions.html#boost_bimap.the_tutorial.useful_functions.replace_and_modify" title="replace and modify">replace |
| and modify</a> |
| </h4></div></div></div> |
| <p> |
| These functions are members of the views of a bimap that are not founded |
| in their standard counterparts. |
| </p> |
| <p> |
| The <code class="computeroutput"><span class="identifier">replace</span></code> family member |
| functions performs in-place replacement of a given element as the following |
| example shows: |
| </p> |
| <p> |
| <a href="../../../../example/tutorial_modify_and_replace.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="keyword">int</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">bm_type</span><span class="special">;</span> |
| <span class="identifier">bm_type</span> <span class="identifier">bm</span><span class="special">;</span> |
| |
| <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">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> |
| |
| <span class="comment">// Replace (1,"one") with (1,"1") using the right map view |
| </span><span class="special">{</span> |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">right_iterator</span> <span class="identifier">it</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">find</span><span class="special">(</span><span class="string">"one"</span><span class="special">);</span> |
| |
| <span class="keyword">bool</span> <span class="identifier">successful_replace</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">replace_key</span><span class="special">(</span> <span class="identifier">it</span><span class="special">,</span> <span class="string">"1"</span> <span class="special">);</span> |
| |
| <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">successful_replace</span> <span class="special">);</span> |
| <span class="special">}</span> |
| |
| <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">value_type</span><span class="special">(</span><span class="number">2</span><span class="special">,</span><span class="string">"two"</span><span class="special">)</span> <span class="special">);</span> |
| |
| <span class="comment">// Fail to replace (1,"1") with (1,"two") using the left map view |
| </span><span class="special">{</span> |
| <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span> <span class="special">==</span> <span class="number">2</span> <span class="special">);</span> |
| |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_iterator</span> <span class="identifier">it</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">find</span><span class="special">(</span><span class="number">1</span><span class="special">);</span> |
| |
| <span class="keyword">bool</span> <span class="identifier">successful_replace</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">replace_data</span><span class="special">(</span> <span class="identifier">it</span><span class="special">,</span> <span class="string">"two"</span> <span class="special">);</span> |
| |
| <a class="co" name="boost_bimap9co" href="useful_functions.html#boost_bimap9"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a><span class="identifier">assert</span><span class="special">(</span> <span class="special">!</span> <span class="identifier">successful_replace</span> <span class="special">);</span> |
| <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span> <span class="special">==</span> <span class="number">2</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_bimap9"></a><a href="#boost_bimap9co"><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">it</span></code> is still valid here, |
| and the bimap was left unchanged </p></td> |
| </tr></table></div> |
| <p> |
| </p> |
| <p> |
| <code class="computeroutput"><span class="identifier">replace</span></code> functions performs |
| this substitution in such a manner that: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| The complexity is constant time if the changed element retains its |
| original order with respect to all views; it is logarithmic otherwise. |
| </li> |
| <li class="listitem"> |
| Iterator and reference validity are preserved. |
| </li> |
| <li class="listitem"> |
| The operation is strongly exception-safe, i.e. the <code class="computeroutput"><span class="identifier">bimap</span></code> |
| remains unchanged if some exception (originated by the system or the |
| user's data types) is thrown. |
| </li> |
| </ul></div> |
| <p> |
| <code class="computeroutput"><span class="identifier">replace</span></code> functions are powerful |
| operations not provided by standard STL containers, and one that is specially |
| handy when strong exception-safety is required. |
| </p> |
| <p> |
| The observant reader might have noticed that the convenience of replace |
| comes at a cost: namely the whole element has to be copied <span class="emphasis"><em>twice</em></span> |
| to do the updating (when retrieving it and inside <code class="computeroutput"><span class="identifier">replace</span></code>). |
| If elements are expensive to copy, this may be quite a computational cost |
| for the modification of just a tiny part of the object. To cope with this |
| situation, Boost.Bimap provides an alternative updating mechanism: <code class="computeroutput"><span class="identifier">modify</span></code> functions. |
| </p> |
| <p> |
| <code class="computeroutput"><span class="identifier">modify</span></code> functions accepts |
| a functor (or pointer to function) taking a reference to the data to be |
| changed, thus eliminating the need for spurious copies. Like <code class="computeroutput"><span class="identifier">replace</span></code> functions, <code class="computeroutput"><span class="identifier">modify</span></code> |
| functions does preserve the internal orderings of all the indices of the |
| <code class="computeroutput"><span class="identifier">bimap</span></code>. However, the semantics |
| of modify functions are not entirely equivalent to replace functions. Consider |
| what happens if a collision occurs as a result of modifying the element, |
| i.e. the modified element clashes with another with respect to some unique |
| view. In the case of <code class="computeroutput"><span class="identifier">replace</span></code> |
| functions, the original value is kept and the method returns without altering |
| the container, but <code class="computeroutput"><span class="identifier">modify</span></code> |
| functions cannot afford such an approach, since the modifying functor leaves |
| no trace of the previous value of the element. Integrity constraints thus |
| lead to the following policy: when a collision happens in the process of |
| calling a modify functions, the element is erased and the method returns |
| false. This difference in behavior between <code class="computeroutput"><span class="identifier">replace</span></code> |
| and <code class="computeroutput"><span class="identifier">modify</span></code> functions has |
| to be considered by the programmer on a case-by-case basis. |
| </p> |
| <p> |
| Boost.Bimap defines new placeholders named <code class="computeroutput"><span class="identifier">_key</span></code> |
| and <code class="computeroutput"><span class="identifier">_data</span></code> to allow a sounder |
| solution. You have to include <code class="computeroutput"><span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">support</span><span class="special">/</span><span class="identifier">lambda</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> |
| to use them. |
| </p> |
| <p> |
| <a href="../../../../example/tutorial_modify_and_replace.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="keyword">int</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">bm_type</span><span class="special">;</span> |
| <span class="identifier">bm_type</span> <span class="identifier">bm</span><span class="special">;</span> |
| <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">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> |
| |
| <span class="comment">// Modify (1,"one") to (1,"1") using the right map view |
| </span><span class="special">{</span> |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">right_iterator</span> <span class="identifier">it</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">find</span><span class="special">(</span><span class="string">"one"</span><span class="special">);</span> |
| |
| <span class="keyword">bool</span> <span class="identifier">successful_modify</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">modify_key</span><span class="special">(</span> <span class="identifier">it</span> <span class="special">,</span> <span class="identifier">_key</span> <span class="special">=</span> <span class="string">"1"</span> <span class="special">);</span> |
| |
| <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">successful_modify</span> <span class="special">);</span> |
| <span class="special">}</span> |
| |
| <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">value_type</span><span class="special">(</span><span class="number">2</span><span class="special">,</span><span class="string">"two"</span><span class="special">)</span> <span class="special">);</span> |
| |
| <span class="comment">// Fail to modify (1,"1") to (1,"two") using the left map view |
| </span><span class="special">{</span> |
| <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span> <span class="special">==</span> <span class="number">2</span> <span class="special">);</span> |
| |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_iterator</span> <span class="identifier">it</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">find</span><span class="special">(</span><span class="number">1</span><span class="special">);</span> |
| |
| <span class="keyword">bool</span> <span class="identifier">successful_modify</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">modify_data</span><span class="special">(</span> <span class="identifier">it</span><span class="special">,</span> <span class="identifier">_data</span> <span class="special">=</span> <span class="string">"two"</span> <span class="special">);</span> |
| |
| <a class="co" name="boost_bimap10co" href="useful_functions.html#boost_bimap10"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a><span class="identifier">assert</span><span class="special">(</span> <span class="special">!</span> <span class="identifier">successful_modify</span> <span class="special">);</span> |
| <span class="identifier">assert</span><span class="special">(</span> <span class="identifier">bm</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span> <span class="special">==</span> <span class="number">1</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_bimap10"></a><a href="#boost_bimap10co"><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">it</span></code> is not longer valid |
| and <code class="computeroutput"><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="string">"1"</span><span class="special">)</span></code> is removed from the bimap </p></td> |
| </tr></table></div> |
| <p> |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="boost_bimap.the_tutorial.useful_functions.retrieval_of_ranges"></a><a class="link" href="useful_functions.html#boost_bimap.the_tutorial.useful_functions.retrieval_of_ranges" title="Retrieval of ranges">Retrieval |
| of ranges</a> |
| </h4></div></div></div> |
| <p> |
| Standard <code class="computeroutput"><span class="identifier">lower_bound</span></code> and |
| <code class="computeroutput"><span class="identifier">upper_bound</span></code> functions can |
| be used to lookup for all the elements in a given range. |
| </p> |
| <p> |
| Suppose we want to retrieve the elements from a <code class="computeroutput"><span class="identifier">bimap</span><span class="special"><</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">></span></code> where the left value is in the range |
| <code class="computeroutput"><span class="special">[</span><span class="number">20</span><span class="special">,</span><span class="number">50</span><span class="special">]</span></code> |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special"><</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">></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> |
| |
| <span class="comment">// ... |
| </span> |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_iterator</span> <span class="identifier">iter_first</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">lower_bound</span><span class="special">(</span><span class="number">20</span><span class="special">);</span> |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_iterator</span> <span class="identifier">iter_second</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">upper_bound</span><span class="special">(</span><span class="number">50</span><span class="special">);</span> |
| |
| <span class="comment">// range [iter_first,iter_second) contains the elements in [20,50] |
| </span></pre> |
| <p> |
| </p> |
| <p> |
| Subtle changes to the code are required when strict inequalities are considered. |
| To retrieve the elements greater than 20 and less than 50, the code has |
| to be rewritten as |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_iterator</span> <span class="identifier">iter_first</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">upper_bound</span><span class="special">(</span><span class="number">20</span><span class="special">);</span> |
| <span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_iterator</span> <span class="identifier">iter_second</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">lower_bound</span><span class="special">(</span><span class="number">50</span><span class="special">);</span> |
| |
| <span class="comment">// range [iter_first,iter_second) contains the elements in (20,50) |
| </span></pre> |
| <p> |
| </p> |
| <p> |
| To add to this complexity, the careful programmer has to take into account |
| that the lower and upper bounds of the interval searched be compatible: |
| for instance, if the lower bound is 50 and the upper bound is 20, the iterators |
| <code class="computeroutput"><span class="identifier">iter_first</span></code> and <code class="computeroutput"><span class="identifier">iter_second</span></code> produced by the code above |
| will be in reverse order, with possibly catastrophic results if a traversal |
| from <code class="computeroutput"><span class="identifier">iter_first</span></code> to <code class="computeroutput"><span class="identifier">iter_second</span></code> is tried. All these details |
| make range searching a tedious and error prone task. |
| </p> |
| <p> |
| The range member function, often in combination with lambda expressions, |
| can greatly help alleviate this situation: |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">bimap</span><span class="special"><</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">></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> |
| |
| <span class="comment">// ... |
| </span> |
| <a class="co" name="boost_bimap11co" href="useful_functions.html#boost_bimap11"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a><span class="identifier">bm_type</span><span class="special">::</span><span class="identifier">left_range_type</span> <span class="identifier">r</span><span class="special">;</span> |
| |
| <a class="co" name="boost_bimap12co" href="useful_functions.html#boost_bimap12"><img src="../../../../../../doc/src/images/callouts/2.png" alt="2" border="0"></a><span class="identifier">r</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">range</span><span class="special">(</span> <span class="number">20</span> <span class="special"><=</span> <span class="identifier">_key</span><span class="special">,</span> <span class="identifier">_key</span> <span class="special"><=</span> <span class="number">50</span> <span class="special">);</span> <span class="comment">// [20,50] |
| </span> |
| <span class="identifier">r</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">range</span><span class="special">(</span> <span class="number">20</span> <span class="special"><</span> <span class="identifier">_key</span><span class="special">,</span> <span class="identifier">_key</span> <span class="special"><</span> <span class="number">50</span> <span class="special">);</span> <span class="comment">// (20,50) |
| </span> |
| <span class="identifier">r</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">range</span><span class="special">(</span> <span class="number">20</span> <span class="special"><=</span> <span class="identifier">_key</span><span class="special">,</span> <span class="identifier">_key</span> <span class="special"><</span> <span class="number">50</span> <span class="special">);</span> <span class="comment">// [20,50) |
| </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_bimap11"></a><a href="#boost_bimap11co"><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">range_type</span></code> is a handy typedef |
| equal to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">iterator</span><span class="special">,</span><span class="identifier">iterator</span><span class="special">></span></code>. |
| <code class="computeroutput"><span class="identifier">const_range_type</span></code> is provided |
| too, and it is equal to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">const_iterator</span><span class="special">,</span><span class="identifier">const_iterator</span><span class="special">></span></code> </p></td> |
| </tr> |
| <tr> |
| <td width="5%" valign="top" align="left"><p><a name="boost_bimap12"></a><a href="#boost_bimap12co"><img src="../../../../../../doc/src/images/callouts/2.png" alt="2" border="0"></a> </p></td> |
| <td valign="top" align="left"><p> _key is a Boost.Lambda placeholder. |
| To use it you have to include <code class="computeroutput"><span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bimap</span><span class="special">/</span><span class="identifier">support</span><span class="special">/</span><span class="identifier">lambda</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code> |
| </p></td> |
| </tr> |
| </table></div> |
| <p> |
| </p> |
| <p> |
| <code class="computeroutput"><span class="identifier">range</span></code> simply accepts predicates |
| specifying the lower and upper bounds of the interval searched. Please |
| consult the reference for a detailed explanation of the permissible predicates |
| passed to range. |
| </p> |
| <p> |
| One or both bounds can be omitted with the special unbounded marker: |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="identifier">r</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">range</span><span class="special">(</span> <span class="number">20</span> <span class="special"><=</span> <span class="identifier">_key</span><span class="special">,</span> <span class="identifier">unbounded</span> <span class="special">);</span> <span class="comment">// [20,inf) |
| </span> |
| <span class="identifier">r</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">range</span><span class="special">(</span> <span class="identifier">unbounded</span> <span class="special">,</span> <span class="identifier">_key</span> <span class="special"><</span> <span class="number">50</span> <span class="special">);</span> <span class="comment">// (-inf,50) |
| </span> |
| <a class="co" name="boost_bimap13co" href="useful_functions.html#boost_bimap13"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a><span class="identifier">r</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">range</span><span class="special">(</span> <span class="identifier">unbounded</span> <span class="special">,</span> <span class="identifier">unbounded</span> <span class="special">);</span> <span class="comment">// (-inf,inf) |
| </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_bimap13"></a><a href="#boost_bimap13co"><img src="../../../../../../doc/src/images/callouts/1.png" alt="1" border="0"></a> </p></td> |
| <td valign="top" align="left"><p> This is equivalent to std::make_pair(s.begin(),s.end()) </p></td> |
| </tr></table></div> |
| <p> |
| </p> |
| <p> |
| <a href="../../../../example/tutorial_range.cpp" target="_top">Go to source code</a> |
| </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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