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<p>
      <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code> is
      currently implemented using a custom aligned storage facility built from <code class="computeroutput"><span class="identifier">alignment_of</span></code> and <code class="computeroutput"><span class="identifier">type_with_alignment</span></code>
      (both from Type Traits). It uses a separate boolean flag to indicate the initialization
      state. Placement new with <code class="computeroutput"><span class="identifier">T</span></code>'s
      copy/move constructor and <code class="computeroutput"><span class="identifier">T</span></code>'s
      destructor are explicitly used to initialize, copy, move and destroy optional
      values. As a result, <code class="computeroutput"><span class="identifier">T</span></code>'s default
      constructor is effectively by-passed, but the exception guarantees are basic.
      It is planned to replace the current implementation with another with stronger
      exception safety, such as a future <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">variant</span></code>.
    </p>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014 Andrzej Krzemie&#324;ski<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>
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new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`<html>`
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Add assignment operators taking an InPlaceFactory to the Detailed Semantics section. Fixes #5378. [SVN r71048] 2011-04-06 20:54:18 +00:00			`<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">`
new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`<title>Implementation Notes</title>`
Updated HTML documentation format using the super-project css and docbook-xsl-1.78.1 2014-04-12 20:54:37 +02:00			`<link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">`
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Add assignment operators taking an InPlaceFactory to the Detailed Semantics section. Fixes #5378. [SVN r71048] 2011-04-06 20:54:18 +00:00			`<link rel="home" href="../index.html" title="Chapter 1. Boost.Optional">`
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new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`<link rel="prev" href="type_requirements.html" title="Type requirements">`
Fix the optional and numeric/conversion docs so they generate valid Docbook XML that can be transformed into PDF's. Regenerated HTML versions of the docs. [SVN r51218] 2009-02-12 14:01:48 +00:00			`<link rel="next" href="dependencies_and_portability.html" title="Dependencies and Portability">`
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optional docs fixes [SVN r43247] 2008-02-14 17:43:52 +00:00			`<table cellpadding="2" width="100%"><tr>`
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Fix the optional and numeric/conversion docs so they generate valid Docbook XML that can be transformed into PDF's. Regenerated HTML versions of the docs. [SVN r51218] 2009-02-12 14:01:48 +00:00			`<td align="center"><a href="../../../../../index.html">Home</a></td>`
Add assignment operators taking an InPlaceFactory to the Detailed Semantics section. Fixes #5378. [SVN r71048] 2011-04-06 20:54:18 +00:00			`<td align="center"><a href="../../../../../libs/libraries.htm">Libraries</a></td>`
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new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`<hr>`
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Add assignment operators taking an InPlaceFactory to the Detailed Semantics section. Fixes #5378. [SVN r71048] 2011-04-06 20:54:18 +00:00			`<a accesskey="p" href="type_requirements.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../index.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="dependencies_and_portability.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>`
new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`</div>`
Rebuilt the HTML documentation using a newer xsltproc 2014-04-11 23:36:24 +02:00			`<div class="section">`
new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`<div class="titlepage"><div><div><h2 class="title" style="clear: both">`
Fix the optional and numeric/conversion docs so they generate valid Docbook XML that can be transformed into PDF's. Regenerated HTML versions of the docs. [SVN r51218] 2009-02-12 14:01:48 +00:00			`<a name="boost_optional.implementation_notes"></a><a class="link" href="implementation_notes.html" title="Implementation Notes">Implementation Notes</a>`
new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`</h2></div></div></div>`
			`<p>`
			`<code class="computeroutput"><span class="identifier">optional</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span></code> is`
			`currently implemented using a custom aligned storage facility built from <code class="computeroutput"><span class="identifier">alignment_of</span></code> and <code class="computeroutput"><span class="identifier">type_with_alignment</span></code>`
			`(both from Type Traits). It uses a separate boolean flag to indicate the initialization`
			`state. Placement new with <code class="computeroutput"><span class="identifier">T</span></code>'s`
Improved documentation. Added some noexcept. 2014-05-07 17:07:12 +02:00			`copy/move constructor and <code class="computeroutput"><span class="identifier">T</span></code>'s`
			`destructor are explicitly used to initialize, copy, move and destroy optional`
			`values. As a result, <code class="computeroutput"><span class="identifier">T</span></code>'s default`
			`constructor is effectively by-passed, but the exception guarantees are basic.`
			`It is planned to replace the current implementation with another with stronger`
			`exception safety, such as a future <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">variant</span></code>.`
new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`</p>`
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Added a test that tests the compiler if references are bound correctly. Also added the second copyright notice. 2014-05-05 19:08:11 +02:00			`<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014 Andrzej Krzemieński<p>`
optional docs fixes [SVN r43247] 2008-02-14 17:43:52 +00:00			`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>`
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new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`</tr></table>`
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Add assignment operators taking an InPlaceFactory to the Detailed Semantics section. Fixes #5378. [SVN r71048] 2011-04-06 20:54:18 +00:00			`<a accesskey="p" href="type_requirements.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../index.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="dependencies_and_portability.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>`
new quickbook docs for optional [SVN r37809] 2007-05-29 06:40:25 +00:00			`</div>`
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