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documented in-place constructors
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<dt><span class="section"><a href="dependencies_and_portability/emplace_operations_in_older_compilers.html">Emplace
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<a name="boost_optional.dependencies_and_portability.emplace_operations_in_older_compilers"></a><a class="link" href="emplace_operations_in_older_compilers.html" title="Emplace operations in older compilers">Emplace
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operations in older compilers</a>
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</h3></div></div></div>
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<p>
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<a name="optional_emplace_workaround"></a>Certain constructors and functions
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in the interface of <code class="computeroutput"><span class="identifier">optional</span></code>
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perform a 'perfect forwarding' of arguments:
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</p>
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<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_t</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">args</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">args</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span> <span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">(</span><span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">args</span><span class="special">);</span>
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</pre>
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<p>
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On compilers that do not support variadic templates, each of these functions
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is substituted with two overloads, one forwarding a single argument, the
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other forwarding zero arguments. This forms the following set:
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</p>
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<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_t</span><span class="special">,</span> <span class="identifier">Arg</span><span class="special">&&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_t</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">,</span> <span class="identifier">Arg</span><span class="special">&&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">(</span><span class="identifier">Arg</span><span class="special">&&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">();</span>
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</pre>
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<p>
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On compilers that do not support rvalue references, each of these functions
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is substituted with three overloadss: taking <code class="computeroutput"><span class="keyword">const</span></code>
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and non-<code class="computeroutput"><span class="keyword">const</span></code> lvalue reference,
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and third forwarding zero arguments. This forms the following set:
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</p>
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<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_t</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">Arg</span><span class="special">&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_t</span><span class="special">,</span> <span class="identifier">Arg</span><span class="special">&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_t</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">Arg</span><span class="special">&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">,</span> <span class="identifier">Arg</span><span class="special">&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="identifier">optional</span><span class="special">(</span><span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">Arg</span><span class="special">&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">Arg</span><span class="special">></span> <span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">(</span><span class="identifier">Arg</span><span class="special">&</span> <span class="identifier">arg</span><span class="special">);</span>
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<span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">();</span>
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</pre>
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<p>
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This workaround addressess about 40% of all use cases. If this is insufficient,
|
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you need to resort to using <a class="link" href="../tutorial/in_place_factories.html" title="In-Place Factories">In-Place
|
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Factories</a>.
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<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2016 Andrzej Krzemieński<p>
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Distributed under the Boost Software License, Version 1.0. (See accompanying
|
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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>)
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<a name="reference_optional_in_place_init"></a><div class="blockquote"><blockquote class="blockquote"><p>
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<code class="computeroutput"><span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span>
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<span class="keyword">explicit</span> <span class="identifier">optional</span><span class="special"><</span><span class="identifier">T</span><span class="special">>::</span><span class="identifier">optional</span><span class="special">(</span> <span class="identifier">in_place_init_t</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">ars</span>
|
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<span class="special">);</span></code>
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</p></blockquote></div>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
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<li class="listitem">
|
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<span class="bold"><strong>Requires:</strong></span> <code class="computeroutput"><span class="identifier">is_constructible_v</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...></span></code> is <code class="computeroutput"><span class="keyword">true</span></code>.
|
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</li>
|
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<li class="listitem">
|
||||
<span class="bold"><strong>Effect:</strong></span> Initializes the contained
|
||||
value as if direct-non-list-initializing an object of type <code class="computeroutput"><span class="identifier">T</span></code> with the arguments <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span><span class="identifier">Args</span><span class="special">>(</span><span class="identifier">args</span><span class="special">)...</span></code>.
|
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</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Postconditions:</strong></span> <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> is initialized.
|
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</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Throws:</strong></span> Any exception thrown by the
|
||||
selected constructor of <code class="computeroutput"><span class="identifier">T</span></code>.
|
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</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Notes: </strong></span> <code class="computeroutput"><span class="identifier">T</span></code>
|
||||
need not be <code class="computeroutput"><span class="identifier">MoveConstructible</span></code>.
|
||||
On compilers that do not suppor variadic templates or rvalue references,
|
||||
this constuctor is available in limited functionality. For details
|
||||
<a class="link" href="../../dependencies_and_portability/emplace_operations_in_older_compilers.html#optional_emplace_workaround">see here</a>.
|
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</li>
|
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<li class="listitem">
|
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<span class="bold"><strong>Example:</strong></span>
|
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<pre class="programlisting"><span class="comment">// creates an std::mutex using its default constructor</span>
|
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<span class="identifier">optional</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">mutex</span><span class="special">></span> <span class="identifier">om</span> <span class="special">{</span><span class="identifier">in_place_init</span><span class="special">};</span>
|
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<span class="identifier">assert</span> <span class="special">(</span><span class="identifier">om</span><span class="special">);</span>
|
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|
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<span class="comment">// creates a unique_lock by calling unique_lock(*om, std::defer_lock)</span>
|
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<span class="identifier">optional</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">unique_lock</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">mutex</span><span class="special">>></span> <span class="identifier">ol</span> <span class="special">{</span><span class="identifier">in_place_init</span><span class="special">,</span> <span class="special">*</span><span class="identifier">om</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">defer_lock</span><span class="special">};</span>
|
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<span class="identifier">assert</span> <span class="special">(</span><span class="identifier">ol</span><span class="special">);</span>
|
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<span class="identifier">assert</span> <span class="special">(!</span><span class="identifier">ol</span><span class="special">-></span><span class="identifier">owns_lock</span><span class="special">());</span>
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</pre>
|
||||
</li>
|
||||
</ul></div>
|
||||
<p>
|
||||
<span class="inlinemediaobject"><img src="../../../images/space.png" alt="space"></span>
|
||||
</p>
|
||||
<a name="reference_optional_in_place_init_if"></a><div class="blockquote"><blockquote class="blockquote"><p>
|
||||
<code class="computeroutput"><span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span>
|
||||
<span class="keyword">explicit</span> <span class="identifier">optional</span><span class="special"><</span><span class="identifier">T</span><span class="special">>::</span><span class="identifier">optional</span><span class="special">(</span> <span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">,</span>
|
||||
<span class="identifier">Args</span><span class="special">&&...</span>
|
||||
<span class="identifier">ars</span> <span class="special">);</span></code>
|
||||
</p></blockquote></div>
|
||||
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Requires:</strong></span> <code class="computeroutput"><span class="identifier">is_constructible_v</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...></span></code> is <code class="computeroutput"><span class="keyword">true</span></code>.
|
||||
</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Effect:</strong></span> If <code class="computeroutput"><span class="identifier">condition</span></code>
|
||||
is <code class="computeroutput"><span class="keyword">true</span></code>, initializes the
|
||||
contained value as if direct-non-list-initializing an object of type
|
||||
<code class="computeroutput"><span class="identifier">T</span></code> with the arguments
|
||||
<code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">forward</span><span class="special"><</span><span class="identifier">Args</span><span class="special">>(</span><span class="identifier">args</span><span class="special">)...</span></code>.
|
||||
</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Postconditions:</strong></span> <code class="computeroutput"><span class="keyword">bool</span><span class="special">(*</span><span class="keyword">this</span><span class="special">)</span> <span class="special">==</span> <span class="identifier">condition</span></code>.
|
||||
</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Throws:</strong></span> Any exception thrown by the
|
||||
selected constructor of <code class="computeroutput"><span class="identifier">T</span></code>.
|
||||
</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Notes: </strong></span> <code class="computeroutput"><span class="identifier">T</span></code>
|
||||
need not be <code class="computeroutput"><span class="identifier">MoveConstructible</span></code>.
|
||||
On compilers that do not suppor variadic templates or rvalue references,
|
||||
this constuctor is available in limited functionality. For details
|
||||
<a class="link" href="../../dependencies_and_portability/emplace_operations_in_older_compilers.html#optional_emplace_workaround">see here</a>.
|
||||
</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Example:</strong></span>
|
||||
<pre class="programlisting"><span class="identifier">optional</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</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">ov1</span> <span class="special">{</span><span class="identifier">in_place_init_if</span><span class="special">,</span> <span class="keyword">false</span><span class="special">,</span> <span class="number">3</span><span class="special">,</span> <span class="string">"A"</span><span class="special">};</span>
|
||||
<span class="identifier">assert</span> <span class="special">(!</span><span class="identifier">ov1</span><span class="special">);</span>
|
||||
|
||||
<span class="identifier">optional</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</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">ov2</span> <span class="special">{</span><span class="identifier">in_place_init_if</span><span class="special">,</span> <span class="keyword">true</span><span class="special">,</span> <span class="number">3</span><span class="special">,</span> <span class="string">"A"</span><span class="special">};</span>
|
||||
<span class="identifier">assert</span> <span class="special">(</span><span class="identifier">ov2</span><span class="special">);</span>
|
||||
<span class="identifier">assert</span> <span class="special">(</span><span class="identifier">ov2</span><span class="special">-></span><span class="identifier">size</span><span class="special">()</span> <span class="special">==</span> <span class="number">3</span><span class="special">);</span>
|
||||
</pre>
|
||||
</li>
|
||||
</ul></div>
|
||||
<p>
|
||||
<span class="inlinemediaobject"><img src="../../../images/space.png" alt="space"></span>
|
||||
</p>
|
||||
@ -1037,15 +1125,8 @@
|
||||
<span class="bold"><strong>Notes:</strong></span> <code class="computeroutput"><span class="identifier">T</span></code>
|
||||
need not be <code class="computeroutput"><span class="identifier">MoveConstructible</span></code>
|
||||
or <code class="computeroutput"><span class="identifier">MoveAssignable</span></code>.
|
||||
On compilers that do not support variadic templates, the signature
|
||||
falls back to two overloads:<code class="computeroutput"><span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span>
|
||||
<span class="identifier">Arg</span><span class="special">></span>
|
||||
<span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">(</span><span class="identifier">Arg</span><span class="special">&&</span> <span class="identifier">arg</span><span class="special">)</span></code> and <code class="computeroutput"><span class="keyword">void</span>
|
||||
<span class="identifier">emplace</span><span class="special">()</span></code>.
|
||||
On compilers that do not support rvalue references, the signature falls
|
||||
back to three overloads: taking <code class="computeroutput"><span class="keyword">const</span></code>
|
||||
and non-<code class="computeroutput"><span class="keyword">const</span></code> lvalue reference,
|
||||
and third with empty function argument list.
|
||||
On compilers that do not suppor variadic templates or rvalue references,
|
||||
this function is available in limited functionality. For details <a class="link" href="../../dependencies_and_portability/emplace_operations_in_older_compilers.html#optional_emplace_workaround">see here</a>.
|
||||
</li>
|
||||
<li class="listitem">
|
||||
<span class="bold"><strong>Example:</strong></span>
|
||||
|
@ -0,0 +1,61 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
||||
<title>Initialization tags</title>
|
||||
<link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
|
||||
<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
|
||||
<link rel="home" href="../../../index.html" title="Boost.Optional">
|
||||
<link rel="up" href="../../../optional/reference/header__boost_optional_optional_hpp_.html" title="Header <boost/optional/optional.hpp>">
|
||||
<link rel="prev" href="../../../optional/reference/header__boost_optional_optional_hpp_.html" title="Header <boost/optional/optional.hpp>">
|
||||
<link rel="next" href="header_optional_optional_values.html" title="Optional Values">
|
||||
</head>
|
||||
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
|
||||
<table cellpadding="2" width="100%"><tr>
|
||||
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td>
|
||||
<td align="center"><a href="../../../../../../../index.html">Home</a></td>
|
||||
<td align="center"><a href="../../../../../../../libs/libraries.htm">Libraries</a></td>
|
||||
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
|
||||
<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
|
||||
<td align="center"><a href="../../../../../../../more/index.htm">More</a></td>
|
||||
</tr></table>
|
||||
<hr>
|
||||
<div class="spirit-nav">
|
||||
<a accesskey="p" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="header_optional_optional_values.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a>
|
||||
</div>
|
||||
<div class="section">
|
||||
<div class="titlepage"><div><div><h4 class="title">
|
||||
<a name="boost_optional.reference.header__boost_optional_optional_hpp_.header_optional_in_place_init"></a><a class="link" href="header_optional_in_place_init.html" title="Initialization tags">Initialization
|
||||
tags</a>
|
||||
</h4></div></div></div>
|
||||
<a name="reference_in_place_init"></a><a name="reference_in_place_init_if"></a><pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span>
|
||||
|
||||
<span class="keyword">class</span> <span class="identifier">in_place_init_t</span> <span class="special">{</span> <span class="comment">/* see below */</span> <span class="special">}</span> <span class="special">;</span>
|
||||
<span class="keyword">const</span> <span class="identifier">in_place_init_t</span> <span class="identifier">in_place_init</span> <span class="special">(</span> <span class="comment">/* see below */</span> <span class="special">)</span> <span class="special">;</span>
|
||||
|
||||
<span class="keyword">class</span> <span class="identifier">in_place_init_if_t</span> <span class="special">{</span> <span class="comment">/*see below*/</span> <span class="special">}</span> <span class="special">;</span>
|
||||
<span class="keyword">const</span> <span class="identifier">in_place_init_if_t</span> <span class="identifier">in_place_init_if</span> <span class="special">(</span> <span class="comment">/*see below*/</span> <span class="special">)</span> <span class="special">;</span>
|
||||
|
||||
<span class="special">}</span>
|
||||
</pre>
|
||||
<p>
|
||||
Classes <code class="computeroutput"><span class="identifier">in_place_init_t</span></code>
|
||||
and <code class="computeroutput"><span class="identifier">in_place_init_if_t</span></code>
|
||||
are empty clsses. Their purpose is to control overload resolution in the
|
||||
initialization of optional objects. They are empty, trivially copyable
|
||||
classes with disabled default constructor.
|
||||
</p>
|
||||
</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 © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2016 Andrzej Krzemieński<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">
|
||||
<a accesskey="p" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="header_optional_optional_values.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a>
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
@ -6,7 +6,7 @@
|
||||
<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
|
||||
<link rel="home" href="../../../index.html" title="Boost.Optional">
|
||||
<link rel="up" href="../../../optional/reference/header__boost_optional_optional_hpp_.html" title="Header <boost/optional/optional.hpp>">
|
||||
<link rel="prev" href="../../../optional/reference/header__boost_optional_optional_hpp_.html" title="Header <boost/optional/optional.hpp>">
|
||||
<link rel="prev" href="header_optional_in_place_init.html" title="Initialization tags">
|
||||
<link rel="next" href="header_optional_optional_refs.html" title="Optional References">
|
||||
</head>
|
||||
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
|
||||
@ -20,7 +20,7 @@
|
||||
</tr></table>
|
||||
<hr>
|
||||
<div class="spirit-nav">
|
||||
<a accesskey="p" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="header_optional_optional_refs.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a>
|
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<a accesskey="p" href="header_optional_in_place_init.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="header_optional_optional_refs.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a>
|
||||
</div>
|
||||
<div class="section">
|
||||
<div class="titlepage"><div><div><h4 class="title">
|
||||
@ -47,7 +47,6 @@
|
||||
|
||||
<span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">T</span><span class="special">&&</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_constructor_move_value"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
|
||||
<span class="comment">// [new in 1.34]</span>
|
||||
<span class="identifier">optional</span> <span class="special">(</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">,</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_constructor_bool_value"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
|
||||
<span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">optional</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_constructor_optional"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
@ -58,6 +57,10 @@
|
||||
|
||||
<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">U</span><span class="special">></span> <span class="keyword">explicit</span> <span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special"><</span><span class="identifier">U</span><span class="special">>&&</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_move_constructor_other_optional"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
|
||||
<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span> <span class="keyword">explicit</span> <span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">in_place_init_t</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">args</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_in_place_init"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
|
||||
<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span> <span class="keyword">explicit</span> <span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">in_place_init_if_t</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">condition</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">args</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_in_place_init_if"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
|
||||
<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">InPlaceFactory</span><span class="special">></span> <span class="keyword">explicit</span> <span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">InPlaceFactory</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_constructor_factory"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
|
||||
<span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">TypedInPlaceFactory</span><span class="special">></span> <span class="keyword">explicit</span> <span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">TypedInPlaceFactory</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics___optional_values.html#reference_optional_constructor_factory"><span class="inlinemediaobject"><img src="../../../images/callouts/R.png" alt="R"></span></a>
|
||||
@ -135,7 +138,7 @@
|
||||
</tr></table>
|
||||
<hr>
|
||||
<div class="spirit-nav">
|
||||
<a accesskey="p" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="header_optional_optional_refs.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a>
|
||||
<a accesskey="p" href="header_optional_in_place_init.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="header_optional_optional_refs.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a>
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
||||
|
@ -28,6 +28,22 @@
|
||||
</h2></div></div></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h0"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_63"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_63">Boost
|
||||
Release 1.63</a>
|
||||
</h4>
|
||||
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
||||
<li class="listitem">
|
||||
Added two new in-place constructors. They work similarly to <code class="computeroutput"><span class="identifier">emplace</span><span class="special">()</span></code>
|
||||
functions: they initialize the contained value by perfect-forwarding the
|
||||
obtained arguments. One constructor always initializes the contained value,
|
||||
the other based on a boolean condition.
|
||||
</li>
|
||||
<li class="listitem">
|
||||
Fixed <a href="https://svn.boost.org/trac/boost/ticket/12203" target="_top">Trac #12203</a>.
|
||||
</li>
|
||||
</ul></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h1"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_62"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_62">Boost
|
||||
Release 1.62</a>
|
||||
</h4>
|
||||
@ -35,7 +51,7 @@
|
||||
Fixed <a href="https://svn.boost.org/trac/boost/ticket/12179" target="_top">Trac #12179</a>.
|
||||
</li></ul></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h1"></a>
|
||||
<a name="boost_optional.relnotes.h2"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_61"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_61">Boost
|
||||
Release 1.61</a>
|
||||
</h4>
|
||||
@ -78,7 +94,7 @@
|
||||
</li>
|
||||
</ul></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h2"></a>
|
||||
<a name="boost_optional.relnotes.h3"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_60"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_60">Boost
|
||||
Release 1.60</a>
|
||||
</h4>
|
||||
@ -89,7 +105,7 @@
|
||||
#11203</a>.
|
||||
</li></ul></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h3"></a>
|
||||
<a name="boost_optional.relnotes.h4"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_59"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_59">Boost
|
||||
Release 1.59</a>
|
||||
</h4>
|
||||
@ -103,7 +119,7 @@
|
||||
</li>
|
||||
</ul></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h4"></a>
|
||||
<a name="boost_optional.relnotes.h5"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_58"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_58">Boost
|
||||
Release 1.58</a>
|
||||
</h4>
|
||||
@ -139,7 +155,7 @@
|
||||
</li>
|
||||
</ul></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h5"></a>
|
||||
<a name="boost_optional.relnotes.h6"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_57"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_57">Boost
|
||||
Release 1.57</a>
|
||||
</h4>
|
||||
@ -149,7 +165,7 @@
|
||||
to fix C++03 compile error on <code class="computeroutput"><span class="identifier">logic_error</span><span class="special">(</span><span class="string">"..."</span><span class="special">)</span></code>"</em></span>.
|
||||
</li></ul></div>
|
||||
<h4>
|
||||
<a name="boost_optional.relnotes.h6"></a>
|
||||
<a name="boost_optional.relnotes.h7"></a>
|
||||
<span class="phrase"><a name="boost_optional.relnotes.boost_release_1_56"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_56">Boost
|
||||
Release 1.56</a>
|
||||
</h4>
|
||||
|
Reference in New Issue
Block a user