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Added the Lazy<T> class, for "lazy" initialization.
2017-11-04 18:43:02 +01:00
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<li class="navelem"><a class="el" href="../../d3/da6/namespace_m_utils.html">MUtils</a></li><li class="navelem"><a class="el" href="../../d0/dce/class_m_utils_1_1_lazy.html">Lazy</a></li> </ul>
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<a href="#pub-methods">Public Member Functions</a> &#124;
<a href="#pro-methods">Protected Member Functions</a> &#124;
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<div class="title">MUtils::Lazy&lt; T &gt; Class Template Reference<span class="mlabels"><span class="mlabel">abstract</span></span></div> </div>
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<p><a class="el" href="../../d0/dce/class_m_utils_1_1_lazy.html" title="Lazy initialization template class. ">Lazy</a> initialization template class.
<a href="../../d0/dce/class_m_utils_1_1_lazy.html#details">More...</a></p>
<p><code>#include &lt;<a class="el" href="../../d8/d4d/_lazy_8h_source.html">Lazy.h</a>&gt;</code></p>
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Public Member Functions</h2></td></tr>
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T &amp;&#160;</td><td class="memItemRight" valign="bottom"><b>operator*</b> (void)</td></tr>
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virtual T *&#160;</td><td class="memItemRight" valign="bottom"><b>create</b> ()=0</td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><h3>template&lt;typename T&gt;<br />
class MUtils::Lazy&lt; T &gt;</h3>
<p><a class="el" href="../../d0/dce/class_m_utils_1_1_lazy.html" title="Lazy initialization template class. ">Lazy</a> initialization template class. </p>
<p>In order to create your own "lazy" initializer, inherit from the <code><a class="el" href="../../d0/dce/class_m_utils_1_1_lazy.html" title="Lazy initialization template class. ">Lazy</a>&lt;T&gt;</code> class an implement the <a class="el" href="../../d2/dad/_hash_8h.html#a330b73d6927d6cd95892712f9396f40e" title="Create instance of a hash function. ">create()</a> function. The lazy-initialized value can be obtained from a <code><a class="el" href="../../d0/dce/class_m_utils_1_1_lazy.html" title="Lazy initialization template class. ">Lazy</a>&lt;T&gt;</code> instance by using the <code>operator*()</code>. Initialization of the value happens when the <code>operator*()</code> is called for the very first time, by invoking the concrete <a class="el" href="../../d2/dad/_hash_8h.html#a330b73d6927d6cd95892712f9396f40e" title="Create instance of a hash function. ">create()</a> function. The return value of <a class="el" href="../../d2/dad/_hash_8h.html#a330b73d6927d6cd95892712f9396f40e" title="Create instance of a hash function. ">create()</a> is then stored internally, so that any subsequent call to the <code>operator*()</code> immediately returns the previously created value.</p>
<p><b>Note on thread-saftey:</b> This class is thread-safe in the sense that all calls to <code>operator*()</code> on the same <code><a class="el" href="../../d0/dce/class_m_utils_1_1_lazy.html" title="Lazy initialization template class. ">Lazy</a>&lt;T&gt;</code> instance, regardless from which thread, are guaranteed to return the exactly same value/object. Still, if the value has <em>not</em> been initialized yet <b>and</b> if multiple threads happen to call <code>operator*()</code> at the same time, then the concrete <a class="el" href="../../d2/dad/_hash_8h.html#a330b73d6927d6cd95892712f9396f40e" title="Create instance of a hash function. ">create()</a> function <em>may</em> be invoked more than once (concurrently and by different threads). In that case, all but one return value of <a class="el" href="../../d2/dad/_hash_8h.html#a330b73d6927d6cd95892712f9396f40e" title="Create instance of a hash function. ">create()</a> are discarded, and all threads eventually receive the same value/object. </p>
</div><hr/>The documentation for this class was generated from the following file:<ul>
<li>include/MUtils/<a class="el" href="../../d8/d4d/_lazy_8h_source.html">Lazy.h</a></li>
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