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| <div class="titlepage"><div><div><h2 class="title" style="clear: both"> |
| <a name="intrusive.usage"></a><a class="link" href="usage.html" title="How to use Boost.Intrusive">How to use Boost.Intrusive</a> |
| </h2></div></div></div> |
| <div class="toc"><dl> |
| <dt><span class="section"><a href="usage.html#intrusive.usage.usage_base_hook">Using base hooks</a></span></dt> |
| <dt><span class="section"><a href="usage.html#intrusive.usage.usage_member_hook">Using member hooks</a></span></dt> |
| <dt><span class="section"><a href="usage.html#intrusive.usage.usage_both_hooks">Using both hooks</a></span></dt> |
| <dt><span class="section"><a href="usage.html#intrusive.usage.usage_lifetime">Object lifetime</a></span></dt> |
| </dl></div> |
| <p> |
| If you plan to insert a class in an intrusive container, you have to make some |
| decisions influencing the class definition itself. Each class that will be |
| used in an intrusive container needs some appropriate data members storing |
| the information needed by the container. We will take a simple intrusive container, |
| the intrusive list (<code class="computeroutput"><a class="link" href="../boost/intrusive/list.html" title="Class template list">boost::intrusive::list</a></code>), |
| for the following examples, but all <span class="bold"><strong>Boost.Intrusive</strong></span> |
| containers are very similar. To compile the example using <code class="computeroutput"><a class="link" href="../boost/intrusive/list.html" title="Class template list">boost::intrusive::list</a></code>, |
| just include: |
| </p> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">intrusive</span><span class="special">/</span><span class="identifier">list</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| </pre> |
| <p> |
| Every class to be inserted in an intrusive container, needs to contain a hook |
| that will offer the necessary data and resources to be insertable in the container. |
| With <span class="bold"><strong>Boost.Intrusive</strong></span> you just choose the hook |
| to be a public base class or a public member of the class to be inserted. |
| <span class="bold"><strong>Boost.Intrusive</strong></span> also offers more flexible |
| hooks for advanced users, as explained in the chapter <a class="link" href="function_hooks.html" title="Using function hooks">Using |
| function hooks</a>, but usually base or member hooks are good enough for |
| most users. |
| </p> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="intrusive.usage.usage_base_hook"></a><a class="link" href="usage.html#intrusive.usage.usage_base_hook" title="Using base hooks">Using base hooks</a> |
| </h3></div></div></div> |
| <p> |
| For <code class="computeroutput"><a class="link" href="../boost/intrusive/list.html" title="Class template list">list</a></code>, you can publicly |
| derive from <code class="computeroutput"><a class="link" href="../boost/intrusive/list_base_hook.html" title="Class template list_base_hook">list_base_hook</a></code>. |
| </p> |
| <pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="special">...</span><span class="identifier">Options</span><span class="special">></span> |
| <span class="keyword">class</span> <span class="identifier">list_base_hook</span><span class="special">;</span> |
| </pre> |
| <p> |
| The class can take several options. <span class="bold"><strong>Boost.Intrusive</strong></span> |
| classes receive arguments in the form <code class="computeroutput"><span class="identifier">option_name</span><span class="special"><</span><span class="identifier">option_value</span><span class="special">></span></code>. You can specify the following options: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <span class="bold"><strong><code class="computeroutput"><span class="identifier">tag</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Tag</span><span class="special">></span></code></strong></span>: |
| this argument serves as a tag, so you can derive from more than one |
| <code class="computeroutput"><a class="link" href="../boost/intrusive/list_base_hook.html" title="Class template list_base_hook">list_base_hook</a></code> |
| and hence put an object in multiple intrusive lists at the same time. |
| An incomplete type can serve as a tag. If you specify two base hooks, |
| you <span class="bold"><strong>must</strong></span> specify a different tag for |
| each one. Example: <code class="computeroutput"><span class="identifier">list_base_hook</span><span class="special"><</span> <span class="identifier">tag</span><span class="special"><</span><span class="identifier">tag1</span><span class="special">></span> <span class="special">></span></code>. |
| If no tag is specified a default one will be used (more on default tags |
| later). |
| </li> |
| <li class="listitem"> |
| <span class="bold"><strong><code class="computeroutput"><span class="identifier">link_mode</span><span class="special"><</span><span class="identifier">link_mode_type</span> |
| <span class="identifier">LinkMode</span><span class="special">></span></code></strong></span>: |
| The second template argument controls the linking policy. <span class="bold"><strong>Boost.Intrusive</strong></span> |
| currently supports 3 modes: <code class="computeroutput"><span class="identifier">normal_link</span></code>, |
| <code class="computeroutput"><span class="identifier">safe_link</span></code> and <code class="computeroutput"><span class="identifier">auto_unlink</span></code>. By default, <code class="computeroutput"><span class="identifier">safe_link</span></code> mode is used. More about |
| these in sections <a class="link" href="safe_hook.html" title="Safe hooks">Safe hooks</a> |
| and <a class="link" href="auto_unlink_hooks.html" title="Auto-unlink hooks">Auto-unlink hooks</a>. |
| Example: <code class="computeroutput"><span class="identifier">list_base_hook</span><span class="special"><</span> <span class="identifier">link_mode</span><span class="special"><</span><span class="identifier">auto_unlink</span><span class="special">></span> <span class="special">></span></code> |
| </li> |
| <li class="listitem"> |
| <span class="bold"><strong><code class="computeroutput"><span class="identifier">void_pointer</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">VoidPointer</span><span class="special">></span></code></strong></span>: |
| this option is the pointer type to be used internally in the hook. The |
| default value is <code class="computeroutput"><span class="keyword">void</span> <span class="special">*</span></code>, |
| which means that raw pointers will be used in the hook. More about this |
| in the section titled <a class="link" href="using_smart_pointers.html" title="Using smart pointers with Boost.Intrusive containers">Using |
| smart pointers with Boost.Intrusive containers</a>. Example: <code class="computeroutput"><span class="identifier">list_base_hook</span><span class="special"><</span> |
| <span class="identifier">void_pointer</span><span class="special"><</span> |
| <span class="identifier">my_smart_ptr</span><span class="special"><</span><span class="keyword">void</span><span class="special">></span> <span class="special">></span></code> |
| </li> |
| </ul></div> |
| <p> |
| For the following examples, let's forget the options and use the default |
| values: |
| </p> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">intrusive</span><span class="special">/</span><span class="identifier">list</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| |
| <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">intrusive</span><span class="special">;</span> |
| |
| <span class="keyword">class</span> <span class="identifier">Foo</span> |
| <span class="comment">//Base hook with default tag, raw pointers and safe_link mode |
| </span> <span class="special">:</span> <span class="keyword">public</span> <span class="identifier">list_base_hook</span><span class="special"><></span> |
| <span class="special">{</span> <span class="comment">/**/</span> <span class="special">};</span> |
| </pre> |
| <p> |
| After that, we can define the intrusive list: |
| </p> |
| <pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="special">...</span><span class="identifier">Options</span><span class="special">></span> |
| <span class="keyword">class</span> <span class="identifier">list</span><span class="special">;</span> |
| </pre> |
| <p> |
| <code class="computeroutput"><span class="identifier">list</span></code> receives the type to |
| be inserted in the container (<code class="computeroutput"><span class="identifier">T</span></code>) |
| as the first parameter and optionally, the user can specify options. We have |
| 3 option types: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <span class="bold"><strong><code class="computeroutput"><span class="identifier">base_hook</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Hook</span><span class="special">></span></code></strong></span> |
| / <span class="bold"><strong><code class="computeroutput"><span class="identifier">member_hook</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">Hook</span><span class="special">,</span> <span class="identifier">Hook</span> <span class="identifier">T</span><span class="special">::*</span> <span class="identifier">PtrToMember</span><span class="special">></span></code></strong></span> |
| / <span class="bold"><strong><code class="computeroutput"><span class="identifier">value_traits</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">ValueTraits</span><span class="special">></span></code></strong></span>: |
| All these options specify the relationship between the type <code class="computeroutput"><span class="identifier">T</span></code> to be inserted in the list and the |
| hook (since we can have several hooks in the same <code class="computeroutput"><span class="identifier">T</span></code> |
| type). <code class="computeroutput"><span class="identifier">member_hook</span></code> will |
| be explained a bit later and <code class="computeroutput"><span class="identifier">value_traits</span></code> |
| will be explained in the <a class="link" href="value_traits.html" title="Containers with custom ValueTraits">Containers |
| with custom ValueTraits</a> section. <span class="bold"><strong>If no option |
| is specified, the container will be configured to use the base hook with |
| the default tag</strong></span>. Some options configured for the hook (the |
| type of the pointers, link mode, etc.) will be propagated to the container. |
| </li> |
| <li class="listitem"> |
| <span class="bold"><strong><code class="computeroutput"><span class="identifier">constant_time_size</span><span class="special"><</span><span class="keyword">bool</span> <span class="identifier">Enabled</span><span class="special">></span></code></strong></span>: |
| Specifies if a constant time <code class="computeroutput"><span class="identifier">size</span><span class="special">()</span></code> function is demanded for the container. |
| This will instruct the intrusive container to store an additional member |
| to keep track of the current size of the container. By default, constant-time |
| size is activated. |
| </li> |
| <li class="listitem"> |
| <span class="bold"><strong><code class="computeroutput"><span class="identifier">size_type</span><span class="special"><</span><span class="keyword">bool</span> <span class="identifier">Enabled</span><span class="special">></span></code></strong></span>: |
| Specifies a type that can hold the size of the container. This type will |
| be the type returned by <code class="computeroutput"><span class="identifier">list</span><span class="special">.</span><span class="identifier">size</span><span class="special">()</span></code> and the type stored in the intrusive |
| container if <code class="computeroutput"><span class="identifier">constant_time_size</span><span class="special"><</span><span class="keyword">true</span><span class="special">></span></code> is requested. The user normally will |
| not need to change this type, but some containers can have a <code class="computeroutput"><span class="identifier">size_type</span></code> that might be different from |
| <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span></code> (for example, STL-like containers |
| use the <code class="computeroutput"><span class="identifier">size_type</span></code> defined |
| by their allocator). <span class="bold"><strong>Boost.Intrusive</strong></span> |
| can be used to implement such containers specifying the the type of the |
| size. By default the type is <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span></code>. |
| </li> |
| </ul></div> |
| <p> |
| Example of a constant-time size intrusive list that will store Foo objects, |
| using the base hook with the default tag: |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">list</span><span class="special"><</span><span class="identifier">Foo</span><span class="special">></span> <span class="identifier">FooList</span><span class="special">;</span> |
| </pre> |
| <p> |
| Example of a intrusive list with non constant-time size that will store Foo |
| objects: |
| </p> |
| <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">list</span><span class="special"><</span><span class="identifier">Foo</span><span class="special">,</span> <span class="identifier">constant_time_size</span><span class="special"><</span><span class="keyword">false</span><span class="special">></span> <span class="special">></span> <span class="identifier">FooList</span><span class="special">;</span> |
| </pre> |
| <p> |
| Remember that the user must specify the base hook if the base hook has no |
| default tag (e.g: if more than one base hook is used): |
| </p> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">intrusive</span><span class="special">/</span><span class="identifier">list</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| |
| <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">intrusive</span><span class="special">;</span> |
| |
| <span class="keyword">struct</span> <span class="identifier">my_tag</span><span class="special">;</span> |
| |
| <span class="keyword">typedef</span> <span class="identifier">list_base_hook</span><span class="special"><</span> <span class="identifier">tag</span><span class="special"><</span><span class="identifier">my_tag</span><span class="special">></span> <span class="special">></span> <span class="identifier">BaseHook</span><span class="special">;</span> |
| <span class="keyword">class</span> <span class="identifier">Foo</span> <span class="special">:</span> <span class="keyword">public</span> <span class="identifier">BaseHook</span> |
| <span class="special">{</span> <span class="comment">/**/</span> <span class="special">};</span> |
| |
| <span class="keyword">typedef</span> <span class="identifier">list</span><span class="special"><</span> <span class="identifier">Foo</span><span class="special">,</span> <span class="identifier">base_hook</span><span class="special"><</span><span class="identifier">BaseHook</span><span class="special">></span> <span class="special">></span> <span class="identifier">FooList</span><span class="special">;</span> |
| </pre> |
| <p> |
| Once the list is defined, we can use it: |
| </p> |
| <pre class="programlisting"><span class="comment">//An object to be inserted in the list |
| </span><span class="identifier">Foo</span> <span class="identifier">foo_object</span><span class="special">;</span> |
| <span class="identifier">FooList</span> <span class="identifier">list</span><span class="special">;</span> |
| |
| <span class="identifier">list</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">object</span><span class="special">);</span> |
| |
| <span class="identifier">assert</span><span class="special">(&</span><span class="identifier">list</span><span class="special">.</span><span class="identifier">front</span><span class="special">()</span> <span class="special">==</span> <span class="special">&</span><span class="identifier">foo_object</span><span class="special">);</span> |
| </pre> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="intrusive.usage.usage_member_hook"></a><a class="link" href="usage.html#intrusive.usage.usage_member_hook" title="Using member hooks">Using member hooks</a> |
| </h3></div></div></div> |
| <p> |
| Sometimes an 'is-a' relationship between list hooks and the list value types |
| is not desirable. In this case, using a member hook as a data member instead |
| of 'disturbing' the hierarchy might be the right way: you can add a public |
| data member <code class="computeroutput"><span class="identifier">list_member_hook</span><span class="special"><...></span></code> to your class. This class can |
| be configured with the same options as <code class="computeroutput"><span class="identifier">list_base_hook</span></code> |
| except the option <code class="computeroutput"><span class="identifier">tag</span></code>: |
| </p> |
| <pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="special">...</span><span class="identifier">Options</span><span class="special">></span> |
| <span class="keyword">class</span> <span class="identifier">list_member_hook</span><span class="special">;</span> |
| </pre> |
| <p> |
| Example: |
| </p> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">intrusive</span><span class="special">/</span><span class="identifier">list</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| |
| <span class="keyword">class</span> <span class="identifier">Foo</span> |
| <span class="special">{</span> |
| <span class="keyword">public</span><span class="special">:</span> |
| <span class="identifier">list_member_hook</span><span class="special"><></span> <span class="identifier">hook_</span><span class="special">;</span> |
| <span class="comment">//... |
| </span><span class="special">};</span> |
| </pre> |
| <p> |
| When member hooks are used, the <code class="computeroutput"><span class="identifier">member_hook</span></code> |
| option is used to configure the list: |
| </p> |
| <pre class="programlisting"><span class="comment">//This option will configure "list" to use the member hook |
| </span><span class="keyword">typedef</span> <span class="identifier">member_hook</span><span class="special"><</span><span class="identifier">Foo</span><span class="special">,</span> <span class="identifier">list_member_hook</span><span class="special"><>,</span> <span class="special">&</span><span class="identifier">Foo</span><span class="special">::</span><span class="identifier">hook_</span><span class="special">></span> <span class="identifier">MemberHookOption</span><span class="special">;</span> |
| |
| <span class="comment">//This list will use the member hook |
| </span><span class="keyword">typedef</span> <span class="identifier">list</span><span class="special"><</span><span class="identifier">Foo</span><span class="special">,</span> <span class="identifier">MemberHookOption</span><span class="special">></span> <span class="identifier">FooList</span><span class="special">;</span> |
| </pre> |
| <p> |
| Now we can use the container: |
| </p> |
| <pre class="programlisting"><span class="comment">//An object to be inserted in the list |
| </span><span class="identifier">Foo</span> <span class="identifier">foo_object</span><span class="special">;</span> |
| <span class="identifier">FooList</span> <span class="identifier">list</span><span class="special">;</span> |
| |
| <span class="identifier">list</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">object</span><span class="special">);</span> |
| |
| <span class="identifier">assert</span><span class="special">(&</span><span class="identifier">list</span><span class="special">.</span><span class="identifier">front</span><span class="special">()</span> <span class="special">==</span> <span class="special">&</span><span class="identifier">foo_object</span><span class="special">);</span> |
| </pre> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="intrusive.usage.usage_both_hooks"></a><a class="link" href="usage.html#intrusive.usage.usage_both_hooks" title="Using both hooks">Using both hooks</a> |
| </h3></div></div></div> |
| <p> |
| You can insert the same object in several intrusive containers at the same |
| time, using one hook per container. This is a full example using base and |
| member hooks: |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">intrusive</span><span class="special">/</span><span class="identifier">list</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">vector</span><span class="special">></span> |
| |
| <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">intrusive</span><span class="special">;</span> |
| |
| <span class="keyword">class</span> <span class="identifier">MyClass</span> <span class="special">:</span> <span class="keyword">public</span> <span class="identifier">list_base_hook</span><span class="special"><></span> |
| <span class="special">{</span> |
| <span class="keyword">int</span> <span class="identifier">int_</span><span class="special">;</span> |
| |
| <span class="keyword">public</span><span class="special">:</span> |
| <span class="identifier">list_member_hook</span><span class="special"><></span> <span class="identifier">member_hook_</span><span class="special">;</span> |
| |
| <span class="identifier">MyClass</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span><span class="special">)</span> <span class="special">:</span> <span class="identifier">int_</span><span class="special">(</span><span class="identifier">i</span><span class="special">)</span> <span class="special">{}</span> |
| <span class="special">};</span> |
| |
| <span class="comment">//Define a list that will store MyClass using the base hook |
| </span><span class="keyword">typedef</span> <span class="identifier">list</span><span class="special"><</span><span class="identifier">MyClass</span><span class="special">></span> <span class="identifier">BaseList</span><span class="special">;</span> |
| |
| <span class="comment">//Define a list that will store MyClass using the member hook |
| </span><span class="keyword">typedef</span> <span class="identifier">member_hook</span> |
| <span class="special"><</span> <span class="identifier">MyClass</span><span class="special">,</span> <span class="identifier">list_member_hook</span><span class="special"><>,</span> <span class="special">&</span><span class="identifier">MyClass</span><span class="special">::</span><span class="identifier">member_hook_</span><span class="special">></span> <span class="identifier">MemberOption</span><span class="special">;</span> |
| <span class="keyword">typedef</span> <span class="identifier">list</span><span class="special"><</span><span class="identifier">MyClass</span><span class="special">,</span> <span class="identifier">MemberOption</span><span class="special">></span> <span class="identifier">MemberList</span><span class="special">;</span> |
| |
| <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> |
| <span class="special">{</span> |
| <span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="identifier">MyClass</span><span class="special">>::</span><span class="identifier">iterator</span> <span class="identifier">VectIt</span><span class="special">;</span> |
| <span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="identifier">MyClass</span><span class="special">>::</span><span class="identifier">reverse_iterator</span> <span class="identifier">VectRit</span><span class="special">;</span> |
| |
| <span class="comment">//Create several MyClass objects, each one with a different value |
| </span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="identifier">MyClass</span><span class="special">></span> <span class="identifier">values</span><span class="special">;</span> |
| <span class="keyword">for</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> <span class="identifier">i</span> <span class="special"><</span> <span class="number">100</span><span class="special">;</span> <span class="special">++</span><span class="identifier">i</span><span class="special">)</span> <span class="identifier">values</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">MyClass</span><span class="special">(</span><span class="identifier">i</span><span class="special">));</span> |
| |
| <span class="identifier">BaseList</span> <span class="identifier">baselist</span><span class="special">;</span> |
| <span class="identifier">MemberList</span> <span class="identifier">memberlist</span><span class="special">;</span> |
| |
| <span class="comment">//Now insert them in the reverse order in the base hook list |
| </span> <span class="keyword">for</span><span class="special">(</span><span class="identifier">VectIt</span> <span class="identifier">it</span><span class="special">(</span><span class="identifier">values</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()),</span> <span class="identifier">itend</span><span class="special">(</span><span class="identifier">values</span><span class="special">.</span><span class="identifier">end</span><span class="special">())</span> |
| <span class="special">;</span> <span class="identifier">it</span> <span class="special">!=</span> <span class="identifier">itend</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">it</span><span class="special">){</span> |
| <span class="identifier">baselist</span><span class="special">.</span><span class="identifier">push_front</span><span class="special">(*</span><span class="identifier">it</span><span class="special">);</span> |
| <span class="special">}</span> |
| |
| <span class="comment">//Now insert them in the same order as in vector in the member hook list |
| </span> <span class="keyword">for</span><span class="special">(</span><span class="identifier">VectIt</span> <span class="identifier">it</span><span class="special">(</span><span class="identifier">values</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()),</span> <span class="identifier">itend</span><span class="special">(</span><span class="identifier">values</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">itend</span><span class="special">;</span> <span class="special">++</span><span class="identifier">it</span><span class="special">)</span> |
| <span class="identifier">memberlist</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(*</span><span class="identifier">it</span><span class="special">);</span> |
| |
| <span class="comment">//Now test lists |
| </span> <span class="special">{</span> |
| <span class="identifier">BaseList</span><span class="special">::</span><span class="identifier">reverse_iterator</span> <span class="identifier">rbit</span><span class="special">(</span><span class="identifier">baselist</span><span class="special">.</span><span class="identifier">rbegin</span><span class="special">()),</span> <span class="identifier">rbitend</span><span class="special">(</span><span class="identifier">baselist</span><span class="special">.</span><span class="identifier">rend</span><span class="special">());</span> |
| <span class="identifier">MemberList</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">mit</span><span class="special">(</span><span class="identifier">memberlist</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()),</span> <span class="identifier">mitend</span><span class="special">(</span><span class="identifier">memberlist</span><span class="special">.</span><span class="identifier">end</span><span class="special">());</span> |
| <span class="identifier">VectIt</span> <span class="identifier">it</span><span class="special">(</span><span class="identifier">values</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()),</span> <span class="identifier">itend</span><span class="special">(</span><span class="identifier">values</span><span class="special">.</span><span class="identifier">end</span><span class="special">());</span> |
| |
| <span class="comment">//Test the objects inserted in the base hook list |
| </span> <span class="keyword">for</span><span class="special">(;</span> <span class="identifier">it</span> <span class="special">!=</span> <span class="identifier">itend</span><span class="special">;</span> <span class="special">++</span><span class="identifier">it</span><span class="special">,</span> <span class="special">++</span><span class="identifier">rbit</span><span class="special">)</span> |
| <span class="keyword">if</span><span class="special">(&*</span><span class="identifier">rbit</span> <span class="special">!=</span> <span class="special">&*</span><span class="identifier">it</span><span class="special">)</span> <span class="keyword">return</span> <span class="number">1</span><span class="special">;</span> |
| |
| <span class="comment">//Test the objects inserted in the member hook list |
| </span> <span class="keyword">for</span><span class="special">(</span><span class="identifier">it</span> <span class="special">=</span> <span class="identifier">values</span><span class="special">.</span><span class="identifier">begin</span><span class="special">();</span> <span class="identifier">it</span> <span class="special">!=</span> <span class="identifier">itend</span><span class="special">;</span> <span class="special">++</span><span class="identifier">it</span><span class="special">,</span> <span class="special">++</span><span class="identifier">mit</span><span class="special">)</span> |
| <span class="keyword">if</span><span class="special">(&*</span><span class="identifier">mit</span> <span class="special">!=</span> <span class="special">&*</span><span class="identifier">it</span><span class="special">)</span> <span class="keyword">return</span> <span class="number">1</span><span class="special">;</span> |
| <span class="special">}</span> |
| |
| <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> |
| <span class="special">}</span> |
| </pre> |
| <p> |
| </p> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="intrusive.usage.usage_lifetime"></a><a class="link" href="usage.html#intrusive.usage.usage_lifetime" title="Object lifetime">Object lifetime</a> |
| </h3></div></div></div> |
| <p> |
| Even if the interface of <code class="computeroutput"><a class="link" href="../boost/intrusive/list.html" title="Class template list">list</a></code> |
| is similar to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">list</span></code>, its usage is a bit different: You |
| always have to keep in mind that you directly store objects in intrusive |
| containers, not copies. The lifetime of a stored object is not bound to or |
| managed by the container: |
| </p> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| When the container gets destroyed before the object, the object is not |
| destroyed, so you have to be careful to avoid resource leaks. |
| </li> |
| <li class="listitem"> |
| When the object is destroyed before the container, your program is likely |
| to crash, because the container contains a pointer to an non-existing |
| object. |
| </li> |
| </ul></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 © 2005 Olaf Krzikalla, 2006-2010 Ion Gaztanaga<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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