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Author SHA1 Message Date
fcbd6abb94 Phoenix Reloaded
[SVN r53348]
2009-05-28 17:15:17 +00:00
fea89e84f3 Fixed most tab and min/max issues from trunk inspection report
[SVN r53141]
2009-05-20 19:19:00 +00:00
2772bfc08d optional docs in cmakeland
[SVN r52251]
2009-04-08 12:09:58 +00:00
361943e033 Add PDF generation options to fix external links to point to the web site.
Added a few more Boostbook based libs that were missed first time around.
Fixed PDF naming issues.

[SVN r51284]
2009-02-17 10:05:58 +00:00
20c9fc8ebe 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
fd38be1636 Fix an incorrectly escaped right arrow.
[SVN r50839]
2009-01-28 09:14:56 +00:00
9f655c6932 Updating dependency information for modularized libraries.
[SVN r49628]
2008-11-07 17:05:27 +00:00
e7d7b014d2 Updating CMake files to latest trunk. Added dependency information for regression tests and a few new macros for internal use.
[SVN r49627]
2008-11-07 17:02:56 +00:00
2af3ec341b Continuing merge of CMake build system files into trunk with the encouragement of Doug Gregor
[SVN r49510]
2008-11-01 13:15:41 +00:00
23 changed files with 270 additions and 302 deletions

22
CMakeLists.txt Normal file
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@ -0,0 +1,22 @@
#----------------------------------------------------------------------------
# This file was automatically generated from the original CMakeLists.txt file
# Add a variable to hold the headers for the library
set (lib_headers
optional.hpp
optional
)
# Add a library target to the build system
boost_library_project(
optional
# SRCDIRS
TESTDIRS test
HEADERS ${lib_headers}
DOCDIRS doc
# DESCRIPTION
MODULARIZED
# AUTHORS
# MAINTAINERS
)

2
doc/CMakeLists.txt Normal file
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@ -0,0 +1,2 @@
boost_add_documentation(optional.qbk)

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@ -12,6 +12,8 @@
import quickbook ;
path-constant images : html ;
xml optional
:
optional.qbk
@ -26,5 +28,8 @@ boostbook standalone
<xsl:param>toc.max.depth=2
<xsl:param>toc.section.depth=2
<xsl:param>chunk.section.depth=1
<format>pdf:<xsl:param>img.src.path=$(images)/
<format>pdf:<xsl:param>boost.url.prefix=http://www.boost.org/doc/libs/release/libs/optional/doc/html
;

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@ -1,23 +1,21 @@
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>A note about
optional&lt;bool&gt;</title>
<title>A note about optional&lt;bool&gt;</title>
<link rel="stylesheet" href="../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
<link rel="start" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<meta name="generator" content="DocBook XSL Stylesheets V1.74.0">
<link rel="home" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="up" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="prev" href="in_place_factories.html" title="In-Place Factories">
<link rel="next" href="exception_safety_guarantees.html" title="Exception Safety
Guarantees">
<link rel="next" href="exception_safety_guarantees.html" title="Exception Safety Guarantees">
</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.htm">Home</a></td>
<td align="center"><a href="../../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/people/people.htm">People</a></td>
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<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
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<td align="center"><a href="../../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
@ -26,8 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.a_note_about_optional_bool_"></a><a href="a_note_about_optional_bool_.html" title="A note about
optional&lt;bool&gt;">A note about
<a name="boost_optional.a_note_about_optional_bool_"></a><a class="link" href="a_note_about_optional_bool_.html" title="A note about optional&lt;bool&gt;">A note about
optional&lt;bool&gt;</a>
</h2></div></div></div>
<p>
@ -36,7 +33,7 @@
</p>
<p>
First, it is functionally similar to a tristate boolean (false,maybe,true)
&#8212;such as <a href="../../../../tribool/index.html" target="_top">boost::tribool</a>&#8212;
&#8212;such as <a href="../../../../../doc/html/tribool.html" target="_top">boost::tribool</a>&#8212;
except that in a tristate boolean, the maybe state <span class="underline">represents
a valid value</span>, unlike the corresponding state of an uninitialized
<code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">bool</span><span class="special">&gt;</span></code>. It
@ -52,8 +49,7 @@
lead to subtle errors due to the implicit <code class="computeroutput"><span class="keyword">bool</span></code>
conversion:
</p>
<pre class="programlisting">
<span class="keyword">void</span> <span class="identifier">foo</span> <span class="special">(</span> <span class="keyword">bool</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span>
<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">foo</span> <span class="special">(</span> <span class="keyword">bool</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span>
<span class="keyword">void</span> <span class="identifier">bar</span><span class="special">()</span>
<span class="special">{</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">bool</span><span class="special">&gt;</span> <span class="identifier">v</span> <span class="special">=</span> <span class="keyword">try</span><span class="special">();</span>

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@ -3,19 +3,18 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Acknowledgments</title>
<link rel="stylesheet" href="../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
<link rel="start" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<meta name="generator" content="DocBook XSL Stylesheets V1.74.0">
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<link rel="prev" href="dependencies_and_portability.html" title="Dependencies
and Portability">
<link rel="prev" href="dependencies_and_portability.html" title="Dependencies and Portability">
</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.htm">Home</a></td>
<td align="center"><a href="../../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/people/people.htm">People</a></td>
<td align="center"><a href="http://www.boost.org/more/faq.htm">FAQ</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>
@ -24,11 +23,11 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.acknowledgments"></a><a href="acknowledgments.html" title="Acknowledgments">Acknowledgments</a>
<a name="boost_optional.acknowledgments"></a><a class="link" href="acknowledgments.html" title="Acknowledgments">Acknowledgments</a>
</h2></div></div></div>
<a name="boost_optional.acknowledgments.pre_formal_review"></a><h4>
<a name="id2645003"></a>
<a href="acknowledgments.html#boost_optional.acknowledgments.pre_formal_review">Pre-formal
<a name="id704954"></a>
<a class="link" href="acknowledgments.html#boost_optional.acknowledgments.pre_formal_review">Pre-formal
review</a>
</h4>
<div class="itemizedlist"><ul type="disc">
@ -66,8 +65,8 @@
</li>
</ul></div>
<a name="boost_optional.acknowledgments.post_formal_review"></a><h4>
<a name="id2645073"></a>
<a href="acknowledgments.html#boost_optional.acknowledgments.post_formal_review">Post-formal
<a name="id705000"></a>
<a class="link" href="acknowledgments.html#boost_optional.acknowledgments.post_formal_review">Post-formal
review</a>
</h4>
<div class="itemizedlist"><ul type="disc">

View File

@ -1,11 +1,10 @@
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Dependencies
and Portability</title>
<title>Dependencies and Portability</title>
<link rel="stylesheet" href="../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
<link rel="start" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<meta name="generator" content="DocBook XSL Stylesheets V1.74.0">
<link rel="home" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="up" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="prev" href="implementation_notes.html" title="Implementation Notes">
<link rel="next" href="acknowledgments.html" title="Acknowledgments">
@ -13,10 +12,10 @@
<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.htm">Home</a></td>
<td align="center"><a href="../../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../libraries.htm">Libraries</a></td>
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<td align="center"><a href="../../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
@ -25,8 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.dependencies_and_portability"></a><a href="dependencies_and_portability.html" title="Dependencies
and Portability">Dependencies
<a name="boost_optional.dependencies_and_portability"></a><a class="link" href="dependencies_and_portability.html" title="Dependencies and Portability">Dependencies
and Portability</a>
</h2></div></div></div>
<p>

View File

@ -3,8 +3,8 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Detailed Semantics</title>
<link rel="stylesheet" href="../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
<link rel="start" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<meta name="generator" content="DocBook XSL Stylesheets V1.74.0">
<link rel="home" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="up" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="prev" href="synopsis.html" title="Synopsis">
<link rel="next" href="examples.html" title="Examples">
@ -12,10 +12,10 @@
<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.htm">Home</a></td>
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<td align="center"><a href="../../../../libraries.htm">Libraries</a></td>
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<td align="center"><a href="../../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
@ -24,7 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.detailed_semantics"></a><a href="detailed_semantics.html" title="Detailed Semantics">Detailed Semantics</a>
<a name="boost_optional.detailed_semantics"></a><a class="link" href="detailed_semantics.html" title="Detailed Semantics">Detailed Semantics</a>
</h2></div></div></div>
<p>
Because <code class="computeroutput"><span class="identifier">T</span></code> might be of reference
@ -64,8 +64,8 @@
<span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
</p>
<a name="boost_optional.detailed_semantics.optional_class_member_functions"></a><h4>
<a name="id2620257"></a>
<a href="detailed_semantics.html#boost_optional.detailed_semantics.optional_class_member_functions">optional
<a name="id677650"></a>
<a class="link" href="detailed_semantics.html#boost_optional.detailed_semantics.optional_class_member_functions">optional
class member functions</a>
</h4>
<p>
@ -97,8 +97,7 @@
called.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">!</span><span class="identifier">def</span> <span class="special">)</span> <span class="special">;</span>
</pre>
</li>
@ -134,8 +133,7 @@
The expression <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">none</span></code> denotes an instance of <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">none_t</span></code> that can be used as the parameter.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">none</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">none</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">n</span><span class="special">(</span><span class="identifier">none</span><span class="special">)</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">!</span><span class="identifier">n</span> <span class="special">)</span> <span class="special">;</span>
</pre>
@ -180,8 +178,7 @@
has no effect.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span><span class="special">(</span><span class="identifier">v</span><span class="special">);</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">*</span><span class="identifier">opt</span> <span class="special">==</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span>
</pre>
@ -212,8 +209,7 @@
<span class="bold"><strong>Throws:</strong></span> Nothing.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">vref</span> <span class="special">=</span> <span class="identifier">v</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span> <span class="identifier">opt</span><span class="special">(</span><span class="identifier">vref</span><span class="special">);</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">*</span><span class="identifier">opt</span> <span class="special">==</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span>
@ -338,8 +334,7 @@
has no effect.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">uninit</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">uninit</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(!</span><span class="identifier">uninit</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">uinit2</span> <span class="special">(</span> <span class="identifier">uninit</span> <span class="special">)</span> <span class="special">;</span>
@ -387,8 +382,7 @@
will reefer to the same object (they alias).
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span> <span class="identifier">uninit</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span> <span class="identifier">uninit</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(!</span><span class="identifier">uninit</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span> <span class="identifier">uinit2</span> <span class="special">(</span> <span class="identifier">uninit</span> <span class="special">)</span> <span class="special">;</span>
@ -454,8 +448,7 @@
has no effect.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">x</span><span class="special">(</span><span class="number">123.4</span><span class="special">);</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">x</span><span class="special">(</span><span class="number">123.4</span><span class="special">);</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">*</span><span class="identifier">x</span> <span class="special">==</span> <span class="number">123.4</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="identifier">y</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span> <span class="special">;</span>
@ -506,7 +499,7 @@
constructor called by the factory throws.
</li>
<li>
<span class="bold"><strong>Notes:</strong></span> See <a href="../index.html#optional_in_place_factories">In-Place
<span class="bold"><strong>Notes:</strong></span> See <a class="link" href="in_place_factories.html" title="In-Place Factories">In-Place
Factories</a>
</li>
<li>
@ -515,8 +508,7 @@
constructor used by the factory; in that case, this constructor has no effect.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="keyword">class</span> <span class="identifier">C</span> <span class="special">{</span> <span class="identifier">C</span> <span class="special">(</span> <span class="keyword">char</span><span class="special">,</span> <span class="keyword">double</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="special">;</span> <span class="special">}</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="keyword">class</span> <span class="identifier">C</span> <span class="special">{</span> <span class="identifier">C</span> <span class="special">(</span> <span class="keyword">char</span><span class="special">,</span> <span class="keyword">double</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="special">;</span> <span class="special">}</span> <span class="special">;</span>
<span class="identifier">C</span> <span class="identifier">v</span><span class="special">(</span><span class="char">'A'</span><span class="special">,</span><span class="number">123.4</span><span class="special">,</span><span class="string">"hello"</span><span class="special">);</span>
@ -574,8 +566,7 @@
<span class="emphasis"><em>copy constructor</em></span> fails, <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> is left properly uninitialized.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">x</span><span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">x</span><span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span> <span class="special">;</span>
@ -613,12 +604,11 @@
</li>
<li>
<span class="bold"><strong>Notes:</strong></span> If <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> was initialized, is is <span class="emphasis"><em>rebound</em></span>
to the new object. See <a href="../index.html#optional_refassign">here</a> for
details on this behavior.
to the new object. See <a class="link" href="rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding semantics for assignment of optional references">here</a>
for details on this behavior.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="keyword">int</span> <span class="identifier">b</span> <span class="special">=</span> <span class="number">2</span> <span class="special">;</span>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">ra</span> <span class="special">=</span> <span class="identifier">a</span> <span class="special">;</span>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">rb</span> <span class="special">=</span> <span class="identifier">b</span> <span class="special">;</span>
@ -687,8 +677,7 @@
<span class="emphasis"><em>copy constructor</em></span> fails, <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> is left properly uninitialized.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span><span class="special">(</span><span class="identifier">v</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
@ -721,12 +710,11 @@
</li>
<li>
<span class="bold"><strong>Notes:</strong></span> If <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> was initialized and so is *rhs, this
is is <span class="emphasis"><em>rebound</em></span> to the new object. See <a href="../index.html#optional_refassign">here</a>
is is <span class="emphasis"><em>rebound</em></span> to the new object. See <a class="link" href="rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding semantics for assignment of optional references">here</a>
for details on this behavior.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="keyword">int</span> <span class="identifier">b</span> <span class="special">=</span> <span class="number">2</span> <span class="special">;</span>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">ra</span> <span class="special">=</span> <span class="identifier">a</span> <span class="special">;</span>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">rb</span> <span class="special">=</span> <span class="identifier">b</span> <span class="special">;</span>
@ -800,8 +788,7 @@
converting constructor fails, <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> is left properly uninitialized.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt0</span><span class="special">(</span><span class="identifier">v</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">U</span><span class="special">&gt;</span> <span class="identifier">opt1</span><span class="special">;</span>
@ -930,8 +917,7 @@
<code class="computeroutput"><span class="identifier">BOOST_ASSERT</span><span class="special">()</span></code>.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span> <span class="special">(</span> <span class="identifier">v</span> <span class="special">);</span>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">u</span> <span class="special">=</span> <span class="special">*</span><span class="identifier">opt</span><span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">u</span> <span class="special">==</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span>
@ -1005,8 +991,7 @@
<span class="bold"><strong>Throws:</strong></span> Nothing.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span><span class="special">,</span> <span class="identifier">z</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span><span class="special">,</span> <span class="identifier">z</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span><span class="special">;</span>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">=</span> <span class="identifier">def</span><span class="special">.</span><span class="identifier">get_value_or</span><span class="special">(</span><span class="identifier">z</span><span class="special">);</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">y</span> <span class="special">==</span> <span class="identifier">z</span> <span class="special">)</span> <span class="special">;</span>
@ -1099,8 +1084,7 @@
<code class="computeroutput"><span class="identifier">BOOST_ASSERT</span><span class="special">()</span></code>.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span> <span class="special">;</span>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">vref</span> <span class="special">=</span> <span class="identifier">v</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span> <span class="identifier">opt</span> <span class="special">(</span> <span class="identifier">vref</span> <span class="special">);</span>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">vref2</span> <span class="special">=</span> <span class="special">*</span><span class="identifier">opt</span><span class="special">;</span>
@ -1173,8 +1157,7 @@
so you should not hold nor delete this pointer
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">v</span><span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span><span class="special">(</span><span class="identifier">v</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span> <span class="identifier">copt</span><span class="special">(</span><span class="identifier">v</span><span class="special">);</span>
<span class="identifier">T</span><span class="special">*</span> <span class="identifier">p</span> <span class="special">=</span> <span class="identifier">opt</span><span class="special">.</span><span class="identifier">get_ptr</span><span class="special">()</span> <span class="special">;</span>
@ -1226,8 +1209,7 @@
<code class="computeroutput"><span class="identifier">BOOST_ASSERT</span><span class="special">()</span></code>.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="keyword">struct</span> <span class="identifier">X</span> <span class="special">{</span> <span class="keyword">int</span> <span class="identifier">mdata</span> <span class="special">;</span> <span class="special">}</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">X</span> <span class="special">{</span> <span class="keyword">int</span> <span class="identifier">mdata</span> <span class="special">;</span> <span class="special">}</span> <span class="special">;</span>
<span class="identifier">X</span> <span class="identifier">x</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;</span> <span class="identifier">opt</span> <span class="special">(</span><span class="identifier">x</span><span class="special">);</span>
<span class="identifier">opt</span><span class="special">-&gt;</span><span class="identifier">mdata</span> <span class="special">=</span> <span class="number">2</span> <span class="special">;</span>
@ -1257,8 +1239,7 @@
<span class="bold"><strong>Throws:</strong></span> Nothing.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">def</span> <span class="special">==</span> <span class="number">0</span> <span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span> <span class="special">(</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">opt</span> <span class="special">);</span>
@ -1294,8 +1275,7 @@
in certain boolean contexts.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">!</span><span class="identifier">opt</span> <span class="special">);</span>
<span class="special">*</span><span class="identifier">opt</span> <span class="special">=</span> <span class="identifier">some_T</span> <span class="special">;</span>
@ -1328,8 +1308,7 @@
<span class="bold"><strong>Throws:</strong></span> Nothing.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">!</span><span class="identifier">def</span><span class="special">.</span><span class="identifier">is_initialized</span><span class="special">()</span> <span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">opt</span> <span class="special">(</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">opt</span><span class="special">.</span><span class="identifier">is_initialized</span><span class="special">()</span> <span class="special">);</span>
@ -1340,8 +1319,8 @@
<span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
</p>
<a name="boost_optional.detailed_semantics.free_functions"></a><h4>
<a name="id2633426"></a>
<a href="detailed_semantics.html#boost_optional.detailed_semantics.free_functions">Free functions</a>
<a name="id692371"></a>
<a class="link" href="detailed_semantics.html#boost_optional.detailed_semantics.free_functions">Free functions</a>
</h4>
<p>
<span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
@ -1364,8 +1343,7 @@
of <code class="computeroutput"><span class="identifier">v</span></code>.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">void</span> <span class="identifier">foo</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">void</span> <span class="identifier">foo</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">foo</span> <span class="special">(</span> <span class="identifier">make_optional</span><span class="special">(</span><span class="number">1</span><span class="special">+</span><span class="number">1</span><span class="special">)</span> <span class="special">)</span> <span class="special">;</span> <span class="comment">// Creates an optional&lt;int&gt;
</span></pre>
@ -1393,8 +1371,7 @@
of <code class="computeroutput"><span class="identifier">v</span></code>.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">calculate_foo</span><span class="special">()</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">calculate_foo</span><span class="special">()</span>
<span class="special">{</span>
<span class="keyword">double</span> <span class="identifier">val</span> <span class="special">=</span> <span class="identifier">compute_foo</span><span class="special">();</span>
<span class="keyword">return</span> <span class="identifier">make_optional</span><span class="special">(</span><span class="identifier">is_not_nan_and_finite</span><span class="special">(</span><span class="identifier">val</span><span class="special">),</span><span class="identifier">val</span><span class="special">);</span>
@ -1441,8 +1418,7 @@
instead
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">x</span><span class="special">(</span><span class="number">12</span><span class="special">);</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">x</span><span class="special">(</span><span class="number">12</span><span class="special">);</span>
<span class="identifier">T</span> <span class="identifier">y</span><span class="special">(</span><span class="number">12</span><span class="special">);</span>
<span class="identifier">T</span> <span class="identifier">z</span><span class="special">(</span><span class="number">21</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def0</span> <span class="special">;</span>
@ -1503,8 +1479,7 @@
instead.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">x</span><span class="special">(</span><span class="number">12</span><span class="special">);</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">x</span><span class="special">(</span><span class="number">12</span><span class="special">);</span>
<span class="identifier">T</span> <span class="identifier">y</span><span class="special">(</span><span class="number">34</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">optX</span><span class="special">(</span><span class="identifier">x</span><span class="special">);</span>
@ -1674,8 +1649,7 @@
If only one is initialized, it has the same basic guarantee as <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="identifier">reset</span><span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="special">)</span></code>.
</li>
<li>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting">
<span class="identifier">T</span> <span class="identifier">x</span><span class="special">(</span><span class="number">12</span><span class="special">);</span>
<span class="bold"><strong>Example:</strong></span><pre class="programlisting"><span class="identifier">T</span> <span class="identifier">x</span><span class="special">(</span><span class="number">12</span><span class="special">);</span>
<span class="identifier">T</span> <span class="identifier">y</span><span class="special">(</span><span class="number">21</span><span class="special">);</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def0</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">def1</span> <span class="special">;</span>

View File

@ -3,8 +3,8 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Development</title>
<link rel="stylesheet" href="../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
<link rel="start" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<meta name="generator" content="DocBook XSL Stylesheets V1.74.0">
<link rel="home" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
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<link rel="prev" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="next" href="synopsis.html" title="Synopsis">
@ -12,10 +12,10 @@
<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.htm">Home</a></td>
<td align="center"><a href="../../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/people/people.htm">People</a></td>
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<td align="center"><a href="../../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
@ -24,7 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.development"></a><a href="development.html" title="Development">Development</a>
<a name="boost_optional.development"></a><a class="link" href="development.html" title="Development">Development</a>
</h2></div></div></div>
<div class="toc"><dl>
<dt><span class="section"><a href="development.html#boost_optional.development.the_models">The models</a></span></dt>
@ -33,7 +33,7 @@
</dl></div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.development.the_models"></a><a href="development.html#boost_optional.development.the_models" title="The models">The models</a>
<a name="boost_optional.development.the_models"></a><a class="link" href="development.html#boost_optional.development.the_models" title="The models">The models</a>
</h3></div></div></div>
<p>
In C++, we can <span class="emphasis"><em>declare</em></span> an object (a variable) of type
@ -170,7 +170,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.development.the_semantics"></a><a href="development.html#boost_optional.development.the_semantics" title="The semantics">The semantics</a>
<a name="boost_optional.development.the_semantics"></a><a class="link" href="development.html#boost_optional.development.the_semantics" title="The semantics">The semantics</a>
</h3></div></div></div>
<p>
Objects of type <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
@ -254,7 +254,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.development.the_interface"></a><a href="development.html#boost_optional.development.the_interface" title="The Interface">The Interface</a>
<a name="boost_optional.development.the_interface"></a><a class="link" href="development.html#boost_optional.development.the_interface" title="The Interface">The Interface</a>
</h3></div></div></div>
<p>
Since the purpose of optional is to allow us to use objects with a formal
@ -292,8 +292,8 @@
itself which are supported by a special interface.
</p>
<a name="boost_optional.development.the_interface.lexically_hinted_value_access_in_the_presence_of_possibly_untitialized_optional_objects__the_operators___and___gt_"></a><h5>
<a name="id2615375"></a>
<a href="development.html#boost_optional.development.the_interface.lexically_hinted_value_access_in_the_presence_of_possibly_untitialized_optional_objects__the_operators___and___gt_">Lexically-hinted
<a name="id672645"></a>
<a class="link" href="development.html#boost_optional.development.the_interface.lexically_hinted_value_access_in_the_presence_of_possibly_untitialized_optional_objects__the_operators___and___gt_">Lexically-hinted
Value Access in the presence of possibly untitialized optional objects: The
operators * and -&gt;</a>
</h5>
@ -357,8 +357,8 @@
incarnated by pointers.
</p>
<a name="boost_optional.development.the_interface.optional_lt_t_gt__as_a_model_of_optionalpointee"></a><h5>
<a name="id2615714"></a>
<a href="development.html#boost_optional.development.the_interface.optional_lt_t_gt__as_a_model_of_optionalpointee">Optional&lt;T&gt;
<a name="id672851"></a>
<a class="link" href="development.html#boost_optional.development.the_interface.optional_lt_t_gt__as_a_model_of_optionalpointee">Optional&lt;T&gt;
as a model of OptionalPointee</a>
</h5>
<p>

View File

@ -3,8 +3,8 @@
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@ -12,10 +12,10 @@
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@ -24,7 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.examples"></a><a href="examples.html" title="Examples">Examples</a>
<a name="boost_optional.examples"></a><a class="link" href="examples.html" title="Examples">Examples</a>
</h2></div></div></div>
<div class="toc"><dl>
<dt><span class="section"><a href="examples.html#boost_optional.examples.optional_return_values">Optional
@ -38,12 +38,10 @@
</dl></div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.examples.optional_return_values"></a><a href="examples.html#boost_optional.examples.optional_return_values" title="Optional
return values">Optional
<a name="boost_optional.examples.optional_return_values"></a><a class="link" href="examples.html#boost_optional.examples.optional_return_values" title="Optional return values">Optional
return values</a>
</h3></div></div></div>
<pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">char</span><span class="special">&gt;</span> <span class="identifier">get_async_input</span><span class="special">()</span>
<pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">char</span><span class="special">&gt;</span> <span class="identifier">get_async_input</span><span class="special">()</span>
<span class="special">{</span>
<span class="keyword">if</span> <span class="special">(</span> <span class="special">!</span><span class="identifier">queue</span><span class="special">.</span><span class="identifier">empty</span><span class="special">()</span> <span class="special">)</span>
<span class="keyword">return</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">char</span><span class="special">&gt;(</span><span class="identifier">queue</span><span class="special">.</span><span class="identifier">top</span><span class="special">());</span>
@ -61,12 +59,10 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.examples.optional_local_variables"></a><a href="examples.html#boost_optional.examples.optional_local_variables" title="Optional
local variables">Optional
<a name="boost_optional.examples.optional_local_variables"></a><a class="link" href="examples.html#boost_optional.examples.optional_local_variables" title="Optional local variables">Optional
local variables</a>
</h3></div></div></div>
<pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">name</span> <span class="special">;</span>
<pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">name</span> <span class="special">;</span>
<span class="keyword">if</span> <span class="special">(</span> <span class="identifier">database</span><span class="special">.</span><span class="identifier">open</span><span class="special">()</span> <span class="special">)</span>
<span class="special">{</span>
<span class="identifier">name</span><span class="special">.</span><span class="identifier">reset</span> <span class="special">(</span> <span class="identifier">database</span><span class="special">.</span><span class="identifier">lookup</span><span class="special">(</span><span class="identifier">employer_name</span><span class="special">)</span> <span class="special">)</span> <span class="special">;</span>
@ -84,12 +80,10 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.examples.optional_data_members"></a><a href="examples.html#boost_optional.examples.optional_data_members" title="Optional
data members">Optional
<a name="boost_optional.examples.optional_data_members"></a><a class="link" href="examples.html#boost_optional.examples.optional_data_members" title="Optional data members">Optional
data members</a>
</h3></div></div></div>
<pre class="programlisting">
<span class="keyword">class</span> <span class="identifier">figure</span>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">figure</span>
<span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
@ -124,12 +118,10 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.examples.bypassing_expensive_unnecessary_default_construction"></a><a href="examples.html#boost_optional.examples.bypassing_expensive_unnecessary_default_construction" title="Bypassing
expensive unnecessary default construction">Bypassing
<a name="boost_optional.examples.bypassing_expensive_unnecessary_default_construction"></a><a class="link" href="examples.html#boost_optional.examples.bypassing_expensive_unnecessary_default_construction" title="Bypassing expensive unnecessary default construction">Bypassing
expensive unnecessary default construction</a>
</h3></div></div></div>
<pre class="programlisting">
<span class="keyword">class</span> <span class="identifier">ExpensiveCtor</span> <span class="special">{</span> <span class="special">...</span> <span class="special">}</span> <span class="special">;</span>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">ExpensiveCtor</span> <span class="special">{</span> <span class="special">...</span> <span class="special">}</span> <span class="special">;</span>
<span class="keyword">class</span> <span class="identifier">Fred</span>
<span class="special">{</span>
<span class="identifier">Fred</span><span class="special">()</span> <span class="special">:</span> <span class="identifier">mLargeVector</span><span class="special">(</span><span class="number">10000</span><span class="special">)</span> <span class="special">{}</span>

View File

@ -1,23 +1,21 @@
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Exception Safety
Guarantees</title>
<title>Exception Safety Guarantees</title>
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@ -26,12 +24,11 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.exception_safety_guarantees"></a><a href="exception_safety_guarantees.html" title="Exception Safety
Guarantees">Exception Safety
<a name="boost_optional.exception_safety_guarantees"></a><a class="link" href="exception_safety_guarantees.html" title="Exception Safety Guarantees">Exception Safety
Guarantees</a>
</h2></div></div></div>
<p>
Because of the current implementation (see <a href="../index.html#optional_implementation_notes">Implementation
Because of the current implementation (see <a class="link" href="implementation_notes.html" title="Implementation Notes">Implementation
Notes</a>), all of the assignment methods:
</p>
<div class="itemizedlist"><ul type="disc">
@ -75,8 +72,7 @@
know that <code class="computeroutput"><span class="identifier">optional</span></code>'s assignment
and reset has the same guarantees.
</p>
<pre class="programlisting">
<span class="comment">//
<pre class="programlisting"><span class="comment">//
</span><span class="comment">// Case 1: Exception thrown during assignment.
</span><span class="comment">//
</span><span class="identifier">T</span> <span class="identifier">v0</span><span class="special">(</span><span class="number">123</span><span class="special">);</span>
@ -116,8 +112,8 @@
<span class="special">}</span>
</pre>
<a name="boost_optional.exception_safety_guarantees.swap"></a><h4>
<a name="id2644478"></a>
<a href="exception_safety_guarantees.html#boost_optional.exception_safety_guarantees.swap">Swap</a>
<a name="id704586"></a>
<a class="link" href="exception_safety_guarantees.html#boost_optional.exception_safety_guarantees.swap">Swap</a>
</h4>
<p>
<code class="computeroutput"><span class="keyword">void</span> <span class="identifier">swap</span><span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;&amp;,</span>

View File

@ -3,20 +3,19 @@
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and Portability">
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@ -25,7 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.implementation_notes"></a><a href="implementation_notes.html" title="Implementation Notes">Implementation Notes</a>
<a name="boost_optional.implementation_notes"></a><a class="link" href="implementation_notes.html" title="Implementation Notes">Implementation Notes</a>
</h2></div></div></div>
<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

View File

@ -3,21 +3,19 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>In-Place Factories</title>
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semantics for assignment of optional references">
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optional&lt;bool&gt;">
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@ -26,7 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.in_place_factories"></a><a href="in_place_factories.html" title="In-Place Factories">In-Place Factories</a>
<a name="boost_optional.in_place_factories"></a><a class="link" href="in_place_factories.html" title="In-Place Factories">In-Place Factories</a>
</h2></div></div></div>
<p>
One of the typical problems with wrappers and containers is that their interfaces
@ -36,8 +34,7 @@
but also requires the existence of a fully constructed object, often temporary,
just to follow the copy from:
</p>
<pre class="programlisting">
<span class="keyword">struct</span> <span class="identifier">X</span>
<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">X</span>
<span class="special">{</span>
<span class="identifier">X</span> <span class="special">(</span> <span class="keyword">int</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="special">;</span>
<span class="special">}</span> <span class="special">;</span>
@ -62,8 +59,7 @@
object right in the container's storage. In this scheme, the user only needs
to supply the arguments to the constructor to use in the wrapped object construction.
</p>
<pre class="programlisting">
<span class="keyword">class</span> <span class="identifier">W</span>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">W</span>
<span class="special">{</span>
<span class="identifier">X</span> <span class="identifier">wrapped_</span> <span class="special">;</span>
@ -96,8 +92,7 @@
<p>
For example, one member of this family looks like:
</p>
<pre class="programlisting">
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span><span class="keyword">class</span> <span class="identifier">A0</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">A1</span><span class="special">&gt;</span>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span><span class="keyword">class</span> <span class="identifier">A0</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">A1</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">TypedInPlaceFactory2</span>
<span class="special">{</span>
<span class="identifier">A0</span> <span class="identifier">m_a0</span> <span class="special">;</span> <span class="identifier">A1</span> <span class="identifier">m_a1</span> <span class="special">;</span>
@ -112,8 +107,7 @@
<p>
A wrapper class aware of this can use it as:
</p>
<pre class="programlisting">
<span class="keyword">class</span> <span class="identifier">W</span>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">W</span>
<span class="special">{</span>
<span class="identifier">X</span> <span class="identifier">wrapped_</span> <span class="special">;</span>
@ -127,7 +121,7 @@
<span class="special">{</span>
<span class="comment">// Wrapped object constructed in-place via a TypedInPlaceFactory.
</span> <span class="comment">// No temporary created.
</span> <span class="identifier">W</span> <span class="special">(</span> <span class="identifier">TypedInPlaceFactory2</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">,</span><span class="keyword">int</span><span class="special">,</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&amp;</span><span class="identifier">rt</span><span class="special">(</span><span class="number">123</span><span class="special">,</span><span class="string">"hello"</span><span class="special">))</span> <span class="special">;</span>
</span> <span class="identifier">W</span> <span class="special">(</span> <span class="identifier">TypedInPlaceFactory2</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">,</span><span class="keyword">int</span><span class="special">,</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;(</span><span class="number">123</span><span class="special">,</span><span class="string">"hello"</span><span class="special">))</span> <span class="special">;</span>
<span class="special">}</span>
</pre>
<p>
@ -152,8 +146,7 @@
This library provides an overloaded set of helper template functions to construct
these factories without requiring unnecessary template parameters:
</p>
<pre class="programlisting">
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">A0</span><span class="special">,...,</span><span class="keyword">class</span> <span class="identifier">AN</span><span class="special">&gt;</span>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">A0</span><span class="special">,...,</span><span class="keyword">class</span> <span class="identifier">AN</span><span class="special">&gt;</span>
<span class="identifier">InPlaceFactoryN</span> <span class="special">&lt;</span><span class="identifier">A0</span><span class="special">,...,</span><span class="identifier">AN</span><span class="special">&gt;</span> <span class="identifier">in_place</span> <span class="special">(</span> <span class="identifier">A0</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">a0</span><span class="special">,</span> <span class="special">...,</span> <span class="identifier">AN</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">aN</span><span class="special">)</span> <span class="special">;</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span><span class="keyword">class</span> <span class="identifier">A0</span><span class="special">,...,</span><span class="keyword">class</span> <span class="identifier">AN</span><span class="special">&gt;</span>
@ -162,8 +155,7 @@
<p>
In-place factories can be used generically by the wrapper and user as follows:
</p>
<pre class="programlisting">
<span class="keyword">class</span> <span class="identifier">W</span>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">W</span>
<span class="special">{</span>
<span class="identifier">X</span> <span class="identifier">wrapped_</span> <span class="special">;</span>

View File

@ -3,20 +3,19 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
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@ -25,7 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.optional_references"></a><a href="optional_references.html" title="Optional references">Optional references</a>
<a name="boost_optional.optional_references"></a><a class="link" href="optional_references.html" title="Optional references">Optional references</a>
</h2></div></div></div>
<p>
This library allows the template parameter <code class="computeroutput"><span class="identifier">T</span></code>

View File

@ -1,11 +1,10 @@
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Rebinding
semantics for assignment of optional references</title>
<title>Rebinding semantics for assignment of optional references</title>
<link rel="stylesheet" href="../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
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@ -13,10 +12,10 @@
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@ -25,8 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.rebinding_semantics_for_assignment_of_optional_references"></a><a href="rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding
semantics for assignment of optional references">Rebinding
<a name="boost_optional.rebinding_semantics_for_assignment_of_optional_references"></a><a class="link" href="rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding semantics for assignment of optional references">Rebinding
semantics for assignment of optional references</a>
</h2></div></div></div>
<p>
@ -34,8 +32,7 @@
the effect is to bind (for the first time) to the object. Clearly, there is
no other choice.
</p>
<pre class="programlisting">
<span class="keyword">int</span> <span class="identifier">x</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<pre class="programlisting"><span class="keyword">int</span> <span class="identifier">x</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="keyword">int</span><span class="special">&amp;</span> <span class="identifier">rx</span> <span class="special">=</span> <span class="identifier">x</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">ora</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">orb</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span> <span class="special">;</span>
@ -47,8 +44,7 @@
If you assign to a bare C++ reference, the assignment is forwarded to the referenced
object; it's value changes but the reference is never rebound.
</p>
<pre class="programlisting">
<span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<pre class="programlisting"><span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="keyword">int</span><span class="special">&amp;</span> <span class="identifier">ra</span> <span class="special">=</span> <span class="identifier">a</span> <span class="special">;</span>
<span class="keyword">int</span> <span class="identifier">b</span> <span class="special">=</span> <span class="number">2</span> <span class="special">;</span>
<span class="keyword">int</span><span class="special">&amp;</span> <span class="identifier">rb</span> <span class="special">=</span> <span class="identifier">b</span> <span class="special">;</span>
@ -62,8 +58,7 @@
the effect is to <span class="bold"><strong>rebind</strong></span> to the new object
instead of assigning the referee. This is unlike bare C++ references.
</p>
<pre class="programlisting">
<span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<pre class="programlisting"><span class="keyword">int</span> <span class="identifier">a</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="keyword">int</span> <span class="identifier">b</span> <span class="special">=</span> <span class="number">2</span> <span class="special">;</span>
<span class="keyword">int</span><span class="special">&amp;</span> <span class="identifier">ra</span> <span class="special">=</span> <span class="identifier">a</span> <span class="special">;</span>
<span class="keyword">int</span><span class="special">&amp;</span> <span class="identifier">rb</span> <span class="special">=</span> <span class="identifier">b</span> <span class="special">;</span>
@ -75,8 +70,8 @@
<span class="identifier">assert</span><span class="special">(</span><span class="identifier">b</span><span class="special">==</span><span class="number">3</span><span class="special">);</span>
</pre>
<a name="boost_optional.rebinding_semantics_for_assignment_of_optional_references.rationale"></a><h4>
<a name="id2640074"></a>
<a href="rebinding_semantics_for_assignment_of_optional_references.html#boost_optional.rebinding_semantics_for_assignment_of_optional_references.rationale">Rationale</a>
<a name="id699431"></a>
<a class="link" href="rebinding_semantics_for_assignment_of_optional_references.html#boost_optional.rebinding_semantics_for_assignment_of_optional_references.rationale">Rationale</a>
</h4>
<p>
Rebinding semantics for the assignment of <span class="emphasis"><em>initialized </em></span>
@ -95,8 +90,7 @@
forwarding assignment to the referenced object (thus changing the referenced
object value but not rebinding), and consider the following code:
</p>
<pre class="programlisting">
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">a</span> <span class="special">=</span> <span class="identifier">get</span><span class="special">();</span>
<pre class="programlisting"><span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">a</span> <span class="special">=</span> <span class="identifier">get</span><span class="special">();</span>
<span class="keyword">int</span> <span class="identifier">x</span> <span class="special">=</span> <span class="number">1</span> <span class="special">;</span>
<span class="keyword">int</span><span class="special">&amp;</span> <span class="identifier">rx</span> <span class="special">=</span> <span class="identifier">x</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">b</span><span class="special">(</span><span class="identifier">rx</span><span class="special">);</span>
@ -134,8 +128,7 @@
for the first time is OK while rebinding is not which is IMO very unlikely.
In such scenario, you can assign the value itself directly, as in:
</p>
<pre class="programlisting">
<span class="identifier">assert</span><span class="special">(!!</span><span class="identifier">opt</span><span class="special">);</span>
<pre class="programlisting"><span class="identifier">assert</span><span class="special">(!!</span><span class="identifier">opt</span><span class="special">);</span>
<span class="special">*</span><span class="identifier">opt</span><span class="special">=</span><span class="identifier">value</span><span class="special">;</span>
</pre>
</div>

View File

@ -3,8 +3,8 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Synopsis</title>
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<link rel="next" href="detailed_semantics.html" title="Detailed Semantics">
@ -12,10 +12,10 @@
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
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<hr>
@ -24,10 +24,9 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.synopsis"></a><a href="synopsis.html" title="Synopsis">Synopsis</a>
<a name="boost_optional.synopsis"></a><a class="link" href="synopsis.html" title="Synopsis">Synopsis</a>
</h2></div></div></div>
<pre class="programlisting">
<span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">optional</span>
@ -36,101 +35,101 @@
<span class="comment">// (If T is of reference type, the parameters and results by reference are by value)
</span>
<span class="identifier">optional</span> <span class="special">()</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_constructor"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">optional</span> <span class="special">()</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_constructor"><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">none_t</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_constructor_none_t"><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">none_t</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_constructor_none_t"><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">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_constructor_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">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_constructor_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">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_constructor_bool_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</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">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.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">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_constructor_optional"><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">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_constructor_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">U</span><span class="special">&gt;</span> <span class="keyword">explicit</span> <span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">U</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_constructor_other_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">U</span><span class="special">&gt;</span> <span class="keyword">explicit</span> <span class="identifier">optional</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">U</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_constructor_other_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">InPlaceFactory</span><span class="special">&gt;</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">&amp;</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.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">&lt;</span><span class="keyword">class</span> <span class="identifier">InPlaceFactory</span><span class="special">&gt;</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">&amp;</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.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">&lt;</span><span class="keyword">class</span> <span class="identifier">TypedInPlaceFactory</span><span class="special">&gt;</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">&amp;</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.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">&lt;</span><span class="keyword">class</span> <span class="identifier">TypedInPlaceFactory</span><span class="special">&gt;</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">&amp;</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_constructor_factory"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">none_t</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_operator_equal_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_operator_equal_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">optional</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_operator_equal_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">optional</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_operator_equal_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">U</span><span class="special">&gt;</span> <span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">U</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_operator_equal_other_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">U</span><span class="special">&gt;</span> <span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">U</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">rhs</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_operator_equal_other_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">InPlaceFactory</span><span class="special">&gt;</span> <span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">InPlaceFactory</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">TypedInPlaceFactory</span><span class="special">&gt;</span> <span class="identifier">optional</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">=</span> <span class="special">(</span> <span class="identifier">TypedInPlaceFactory</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">f</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">get</span><span class="special">()</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">get</span><span class="special">()</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="comment">// [new in 1.34]
</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get_value_or</span><span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="keyword">default</span> <span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get_value_or_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get_value_or</span><span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="keyword">default</span> <span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get_value_or_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="keyword">operator</span> <span class="special">-&gt;()</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_operator_arrow"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">*</span> <span class="keyword">operator</span> <span class="special">-&gt;()</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_operator_arrow"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="keyword">operator</span> <span class="special">-&gt;()</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_operator_arrow"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">*</span> <span class="keyword">operator</span> <span class="special">-&gt;()</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_operator_arrow"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">*()</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">*()</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">*()</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">&amp;</span> <span class="keyword">operator</span> <span class="special">*()</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">get_ptr</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">*</span> <span class="identifier">get_ptr</span><span class="special">()</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">get_ptr</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="identifier">T</span><span class="special">*</span> <span class="identifier">get_ptr</span><span class="special">()</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">operator</span> <span class="identifier">unspecified</span><span class="special">-</span><span class="keyword">bool</span><span class="special">-</span><span class="identifier">type</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_operator_bool"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">operator</span> <span class="identifier">unspecified</span><span class="special">-</span><span class="keyword">bool</span><span class="special">-</span><span class="identifier">type</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_operator_bool"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">!()</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_operator_not"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">bool</span> <span class="keyword">operator</span><span class="special">!()</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_operator_not"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="comment">// deprecated methods
</span>
<span class="comment">// (deprecated)
</span> <span class="keyword">void</span> <span class="identifier">reset</span><span class="special">()</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_reset"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</span> <span class="keyword">void</span> <span class="identifier">reset</span><span class="special">()</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_reset"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="comment">// (deprecated)
</span> <span class="keyword">void</span> <span class="identifier">reset</span> <span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_reset_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</span> <span class="keyword">void</span> <span class="identifier">reset</span> <span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_reset_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="comment">// (deprecated)
</span> <span class="keyword">bool</span> <span class="identifier">is_initialized</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_is_initialized"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</span> <span class="keyword">bool</span> <span class="identifier">is_initialized</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_is_initialized"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="special">};</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">==</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_operator_compare_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">==</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_operator_compare_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">!=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_operator_compare_not_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">!=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_operator_compare_not_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&lt;</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_operator_compare_less_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&lt;</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_operator_compare_less_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&gt;</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_operator_compare_greater_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&gt;</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_operator_compare_greater_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&lt;=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_operator_compare_less_or_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&lt;=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_operator_compare_less_or_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&gt;=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_operator_compare_greater_or_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">bool</span> <span class="keyword">operator</span> <span class="special">&gt;=</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_operator_compare_greater_or_equal_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="comment">// [new in 1.34]
</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">make_optional</span> <span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_make_optional_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">make_optional</span> <span class="special">(</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_make_optional_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="comment">// [new in 1.34]
</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">make_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">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_make_optional_bool_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="identifier">make_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">&amp;</span> <span class="identifier">v</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_make_optional_bool_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="comment">// [new in 1.34]
</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get_optional_value_or</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span><span class="special">,</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="keyword">default</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get_value_or_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get_optional_value_or</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span><span class="special">,</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="keyword">default</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get_value_or_value"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span><span class="special">&amp;</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span><span class="special">*</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;*</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span><span class="special">*</span> <span class="identifier">get</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;*</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">get_pointer</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">get_pointer</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span><span class="special">*</span> <span class="identifier">get_pointer</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="identifier">T</span><span class="special">*</span> <span class="identifier">get_pointer</span> <span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="special">&amp;</span> <span class="identifier">opt</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_optional_get_ptr"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">void</span> <span class="identifier">swap</span><span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a href="detailed_semantics.html#reference_swap_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">inline</span> <span class="keyword">void</span> <span class="identifier">swap</span><span class="special">(</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;&amp;</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;&amp;</span> <span class="identifier">y</span> <span class="special">)</span> <span class="special">;</span> <a class="link" href="detailed_semantics.html#reference_swap_optional_optional"><span class="inlinemediaobject"><img src="../images/callouts/R.png" alt="R"></span></a>
<span class="special">}</span> <span class="comment">// namespace boost
</span></pre>

View File

@ -3,20 +3,19 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Type requirements</title>
<link rel="stylesheet" href="../boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
<link rel="start" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<meta name="generator" content="DocBook XSL Stylesheets V1.74.0">
<link rel="home" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="up" href="../index.html" title="Chapter<65>1.<2E>Boost.Optional">
<link rel="prev" href="exception_safety_guarantees.html" title="Exception Safety
Guarantees">
<link rel="prev" href="exception_safety_guarantees.html" title="Exception Safety Guarantees">
<link rel="next" href="implementation_notes.html" title="Implementation Notes">
</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.htm">Home</a></td>
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<hr>
@ -25,7 +24,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_optional.type_requirements"></a><a href="type_requirements.html" title="Type requirements">Type requirements</a>
<a name="boost_optional.type_requirements"></a><a class="link" href="type_requirements.html" title="Type requirements">Type requirements</a>
</h2></div></div></div>
<p>
In general, <code class="computeroutput"><span class="identifier">T</span></code> must be <a href="../../../../utility/CopyConstructible.html" target="_top">Copy Constructible</a> and

View File

@ -3,17 +3,17 @@
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Chapter<EFBFBD>1.<2E>Boost.Optional</title>
<link rel="stylesheet" href="boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.70.1">
<link rel="start" href="index.html" title="Chapter<65>1.<2E>Boost.Optional">
<meta name="generator" content="DocBook XSL Stylesheets V1.74.0">
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<link rel="next" href="boost_optional/development.html" title="Development">
</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.htm">Home</a></td>
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<td align="center"><a href="../../../libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/people/people.htm">People</a></td>
<td align="center"><a href="http://www.boost.org/more/faq.htm">FAQ</a></td>
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
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<hr>
@ -27,7 +27,7 @@
</h3></div></div>
<div><p class="copyright">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</p></div>
<div><div class="legalnotice">
<a name="id2604939"></a><p>
<a name="id663349"></a><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>
@ -73,7 +73,7 @@
</div>
<div class="section" lang="en">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="optional.motivation"></a><a href="index.html#optional.motivation" title="Motivation">Motivation</a>
<a name="optional.motivation"></a><a class="link" href="index.html#optional.motivation" title="Motivation">Motivation</a>
</h2></div></div></div>
<p>
Consider these functions which should return a value but which might not have
@ -142,16 +142,14 @@
the function would conceptually return. For example, the last two functions
could have the following interface:
</p>
<pre class="programlisting">
<span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">char</span><span class="special">,</span><span class="keyword">bool</span><span class="special">&gt;</span> <span class="identifier">get_async_input</span><span class="special">();</span>
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="keyword">char</span><span class="special">,</span><span class="keyword">bool</span><span class="special">&gt;</span> <span class="identifier">get_async_input</span><span class="special">();</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">point</span><span class="special">,</span><span class="keyword">bool</span><span class="special">&gt;</span> <span class="identifier">polygon</span><span class="special">::</span><span class="identifier">get_any_point_effectively_inside</span><span class="special">();</span>
</pre>
<p>
These functions use a consistent interface for dealing with possibly inexistent
results:
</p>
<pre class="programlisting">
<span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">point</span><span class="special">,</span><span class="keyword">bool</span><span class="special">&gt;</span> <span class="identifier">p</span> <span class="special">=</span> <span class="identifier">poly</span><span class="special">.</span><span class="identifier">get_any_point_effectively_inside</span><span class="special">();</span>
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">point</span><span class="special">,</span><span class="keyword">bool</span><span class="special">&gt;</span> <span class="identifier">p</span> <span class="special">=</span> <span class="identifier">poly</span><span class="special">.</span><span class="identifier">get_any_point_effectively_inside</span><span class="special">();</span>
<span class="keyword">if</span> <span class="special">(</span> <span class="identifier">p</span><span class="special">.</span><span class="identifier">second</span> <span class="special">)</span>
<span class="identifier">flood_fill</span><span class="special">(</span><span class="identifier">p</span><span class="special">.</span><span class="identifier">first</span><span class="special">);</span>
</pre>
@ -166,15 +164,9 @@
</div>
<p>
</p>
<a name="optional_refassign"></a><p>
</p>
<a name="optional_in_place_factories"></a><p>
</p>
<a name="optional_implementation_notes"></a><p>
</p>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"><p><small>Last revised: February 12, 2008 at 22:47:14 GMT</small></p></td>
<td align="left"><p><small>Last revised: February 09, 2009 at 11:55:08 GMT</small></p></td>
<td align="right"><div class="copyright-footer"></div></td>
</tr></table>
<hr>

View File

@ -10,8 +10,6 @@
[#optional_implementation_notes]
[section Implementation Notes]
`optional<T>` is currently implemented using a custom aligned storage facility

View File

@ -331,7 +331,7 @@ factory.
* [*Postconditions: ] `*this` is [_initialized] and its value is ['directly given]
from the factory `f` (i.e., the value [_is not copied]).
* [*Throws:] Whatever the `T` constructor called by the factory throws.
* [*Notes:] See [link optional_in_place_factories In-Place Factories]
* [*Notes:] See [link boost_optional.in_place_factories In-Place Factories]
* [*Exception Safety:] Exceptions can only be thrown during the call to
the `T` constructor used by the factory; in that case, this constructor has
no effect.
@ -385,7 +385,7 @@ __SPACE__
* [*Postconditions: ] `*this` is initialized and it references the same
object referenced by `rhs`.
* [*Notes:] If `*this` was initialized, is is ['rebound] to the new object.
See [link optional_refassign here] for details on this behavior.
See [link boost_optional.rebinding_semantics_for_assignment_of_optional_references here] for details on this behavior.
* [*Example:]
``
int a = 1 ;
@ -444,7 +444,7 @@ __SPACE__
references the same object referenced by `*rhs`; otherwise, `*this` is
uninitialized (and references no object).
* [*Notes:] If `*this` was initialized and so is *rhs, this is is ['rebound] to
the new object. See [link optional_refassign here] for details on this behavior.
the new object. See [link boost_optional.rebinding_semantics_for_assignment_of_optional_references here] for details on this behavior.
* [*Example:]
``
int a = 1 ;

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@ -23,8 +23,6 @@ rather than the reference itself.
[endsect]
[#optional_refassign]
[section Rebinding semantics for assignment of optional references]
If you assign to an ['uninitialized ] `optional<T&>` the effect is to bind (for
@ -112,8 +110,6 @@ In such scenario, you can assign the value itself directly, as in:
[endsect]
[#optional_in_place_factories]
[section In-Place Factories]
One of the typical problems with wrappers and containers is that their
@ -205,7 +201,7 @@ A wrapper class aware of this can use it as:
{
// Wrapped object constructed in-place via a TypedInPlaceFactory.
// No temporary created.
W ( TypedInPlaceFactory2<X,int,std::string&rt(123,"hello")) ;
W ( TypedInPlaceFactory2<X,int,std::string>(123,"hello")) ;
}
The factories are divided in two groups:
@ -288,7 +284,7 @@ instead, it won't compile).
[section Exception Safety Guarantees]
Because of the current implementation (see [link optional_implementation_notes Implementation Notes]), all of the assignment methods:
Because of the current implementation (see [link boost_optional.implementation_notes Implementation Notes]), all of the assignment methods:
* `optional<T>::operator= ( optional<T> const& )`
* `optional<T>::operator= ( T const& )`

1
module.cmake Normal file
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@ -0,0 +1 @@
boost_module(optional DEPENDS utility)

16
test/CMakeLists.txt Normal file
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@ -0,0 +1,16 @@
boost_additional_test_dependencies(optional BOOST_DEPENDS test tuple)
boost_test_run(optional_test)
boost_test_run(optional_test_tie)
boost_test_run(optional_test_ref)
boost_test_run(optional_test_inplace)
boost_test_run(optional_test_io)
boost_test_compile_fail(optional_test_fail1)
boost_test_compile_fail(optional_test_fail3a)
boost_test_compile_fail(optional_test_fail3b)
boost_test_compile_fail(optional_test_ref_fail1)
boost_test_compile_fail(optional_test_ref_fail3)
boost_test_compile_fail(optional_test_ref_fail4)
boost_test_compile_fail(optional_test_inplace_fail)
boost_test_compile_fail(optional_test_inplace_fail2)

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@ -342,14 +342,14 @@ void test_binding()
int i = 0 ;
optional<int&> ori1 = i ;
BOOST_CHECK( &(*ori1) == &i ) ;
optional<int&> ori2(i) ;
BOOST_CHECK( &(*ori2) == &i ) ;
int const ci = 0 ;
optional<int const&> orci1 = ci ;
BOOST_CHECK( &(*orci1) == &ci ) ;
optional<int const&> orci2(ci) ;
BOOST_CHECK( &(*orci2) == &ci ) ;
}
@ -360,7 +360,7 @@ int test_main( int, char* [] )
{
test_with_class_type();
test_with_builtin_types();
test_binding();
test_binding();
}
catch ( ... )
{