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Added emplace(void) for older compilers

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Andrzej Krzemienski
2015-05-15 16:27:40 +02:00
parent 339202a8fb
commit 8ca74951b0
7 changed files with 65 additions and 33 deletions
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doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics.html
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@ -1336,23 +1336,26 @@
<li class="listitem">
<span class="bold"><strong>Throws:</strong></span> Whatever the selected <code class="computeroutput"><span class="identifier">T</span></code>'s constructor throws.
</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>
or <code class="computeroutput"><span class="identifier">MoveAssignable</span></code>.
On compilers that do not support variadic templates, the signature
falls back to single-argument: <code class="computeroutput"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span>
<span class="identifier">Arg</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">(</span><span class="identifier">Arg</span><span class="special">&amp;&amp;</span> <span class="identifier">arg</span><span class="special">)</span></code>. On compilers that do not support
rvalue references, the signature falls back to two overloads: taking
<code class="computeroutput"><span class="keyword">const</span></code> and non-<code class="computeroutput"><span class="keyword">const</span></code> lvalue reference.
</li>
<li class="listitem">
<span class="bold"><strong>Exception Safety:</strong></span> If an exception
is thrown during the initialization of <code class="computeroutput"><span class="identifier">T</span></code>,
<code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code>
is <span class="emphasis"><em>uninitialized</em></span>.
</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>
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">&lt;</span><span class="keyword">class</span>
<span class="identifier">Arg</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">emplace</span><span class="special">(</span><span class="identifier">Arg</span><span class="special">&amp;&amp;</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.
</li>
<li class="listitem">
<span class="bold"><strong>Example:</strong></span>
<pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>