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31 Commits

Author SHA1 Message Date
429e88d2b9 Branch for merging Boost.Build and Boost.Jam completely.
[SVN r59143]
2010-01-19 20:47:20 +00:00
a63dbe0f14 Rebuild optional docs.
[SVN r57812]
2009-11-20 10:26:23 +00:00
066dd6f345 rm cmake from trunk. I'm not entirely sure this is necessary to satisfy the inspect script, but I'm not taking any chances, and it is easy to put back
[SVN r56942]
2009-10-17 02:07:38 +00:00
4e628ed4a6 Copyrights on CMakeLists.txt to keep them from clogging up the inspect
reports.  This is essentially the same commit as r55095 on the release
branch.



[SVN r55159]
2009-07-26 00:49:56 +00:00
8682f2bbaa avoid C style casts
[SVN r53671]
2009-06-06 09:42:41 +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
3ebabcb2d8 Fixed syntax of optional_swap_should_use_default_constructor and swap template specializations that I added 2 days ago (changeset [45265]). Was accepted by MSVC, but rejected by other compilers.
[SVN r45295]
2008-05-12 13:29:52 +00:00
63f6e7f45e Added more optional::swap tests, especially on self swap, on specializing boost::swap for optional<T>, and on swapping optional<T> when T is a template class.
[SVN r45265]
2008-05-10 14:53:51 +00:00
43eac5bb12 Added forward declaration of boost::optional_swap_should_use_default_constructor.
[SVN r45264]
2008-05-10 14:42:49 +00:00
74674531c8 Replaced "using std::swap" by "using boost::swap" within optional::swap member function, hoping to fix GCC test failures, as mentioned at http://article.gmane.org/gmane.comp.lib.boost.devel/174350 "Re: [optional] problems with swap()"
[SVN r44826]
2008-04-27 21:09:50 +00:00
a4572497be Added forward declaration of optional<T>'s boost::swap overload, as mentioned at http://article.gmane.org/gmane.comp.lib.boost.devel/174350 "Re: [optional] problems with swap()"
[SVN r44825]
2008-04-27 21:07:10 +00:00
951b49f992 Merge in documentation fixes. Apart from the change to optional's documenation
Jamfile, which I included by mistake.

Fixes #1659, #1661, #1684, #1685, 1687, #1690, #1801

I wrote about this at:

http://lists.boost.org/Archives/boost/2008/04/136405.php

Merged revisions 44585-44806 via svnmerge from 
https://svn.boost.org/svn/boost/branches/doc

........
  r44585 | danieljames | 2008-04-19 16:25:27 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix broken link to vacpp in bjam docs. Refs #1512
........
  r44586 | danieljames | 2008-04-19 16:27:36 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix broken link to bcpp in bjam docs. Refs #1513
........
  r44587 | danieljames | 2008-04-19 16:33:58 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  DateTime documentation - Fix a link to the serialization library. Refs #1659
........
  r44588 | danieljames | 2008-04-19 16:35:36 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix some links in interprocess & intrusive. Refs #1661
........
  r44589 | danieljames | 2008-04-19 16:37:39 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix some links in the python docs. Refs #1684.
........
  r44590 | danieljames | 2008-04-19 16:38:29 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Work around a quickbook bug which is affecting the python docs. Refs #1684.
........
  r44591 | danieljames | 2008-04-19 16:39:34 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix a broken link in the numeric conversion docs. Refs #1685
........
  r44592 | danieljames | 2008-04-19 16:40:45 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix some links in the optional docs. Refs #1687
........
  r44593 | danieljames | 2008-04-19 16:42:09 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix link to the hash documentation from bimap. Refs #1690
........
  r44599 | danieljames | 2008-04-19 18:07:33 +0100 (Sat, 19 Apr 2008) | 2 lines
  
  Fix a typo in the format library. Refs #1801
........
  r44600 | danieljames | 2008-04-19 19:20:59 +0100 (Sat, 19 Apr 2008) | 1 line
  
  Initialise svnmerge.
........
  r44641 | danieljames | 2008-04-20 18:59:47 +0100 (Sun, 20 Apr 2008) | 2 lines
  
  Fix the lincense url in shared container iterator documentation.
........
  r44642 | danieljames | 2008-04-20 19:00:00 +0100 (Sun, 20 Apr 2008) | 2 lines
  
  Fix image link in the mpi documentation.
........
  r44643 | danieljames | 2008-04-20 19:00:11 +0100 (Sun, 20 Apr 2008) | 2 lines
  
  Fix a typo in the spirit docs.
........
  r44644 | danieljames | 2008-04-20 19:00:23 +0100 (Sun, 20 Apr 2008) | 2 lines
  
  Escape the slash so that quickbook doesn't think it the start of an italic section, and mess up the link. Refs #1844
........
  r44647 | danieljames | 2008-04-20 19:39:47 +0100 (Sun, 20 Apr 2008) | 2 lines
  
  Fix another typo in spirit docs.
........


[SVN r44807]
2008-04-27 07:39:49 +00:00
1afed544db Added unit tests, testing optional<T> swap improvements of revision [44766]
[SVN r44767]
2008-04-25 16:52:34 +00:00
66c366d18a Improved swap for optional<T>, co-written by Thorsten and Fernando: added support for tweaking whether swap should use T's default constructor. Added swap member function. Discussed at Boost developers' mailing list, "[optional] problems with swap()", http://lists.boost.org/Archives/boost/2008/04/135882.php
[SVN r44766]
2008-04-25 16:50:32 +00:00
472a68c920 redirect optional docs to new version
[SVN r43248]
2008-02-14 17:44:21 +00:00
3e33d4a200 optional docs fixes
[SVN r43247]
2008-02-14 17:43:52 +00:00
95c864e119 Cast to base added to avoid a call to the convertir constructor/assignment (see Tickes 1419 and 1420)
[SVN r41381]
2007-11-25 20:26:14 +00:00
9afdbe65e7 // Add or correct comment identifying Boost library this header is associated with.
[SVN r41173]
2007-11-17 20:13:16 +00:00
f6518df0c4 Get rid of .cvsignore files
[SVN r41107]
2007-11-15 15:20:27 +00:00
05a685b035 Fixed intention in the added binding test
[SVN r40860]
2007-11-06 22:21:43 +00:00
3b5b5d82a0 Added test to ensure proper binding of optional references (in reference to Ticket 1301)
[SVN r40707]
2007-11-02 23:41:37 +00:00
06ba35cd42 Fixed error reported by Edward Diener
[SVN r40706]
2007-11-02 23:06:42 +00:00
3499d477dc Merged changests from RC_1_34_0 - base rev 33417
[SVN r40705]
2007-11-02 22:56:23 +00:00
a690c8e7a2 Merged changests from RC_1_34_0 - base rev 33417
[SVN r40704]
2007-11-02 22:55:49 +00:00
56 changed files with 1333 additions and 2471 deletions

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@ -12,6 +12,8 @@
import quickbook ;
path-constant images : html ;
xml optional
:
optional.qbk
@ -21,8 +23,13 @@ boostbook standalone
:
optional
:
<xsl:param>toc.max.depth=1
<xsl:param>toc.section.depth=1
<xsl:param>boost.root=../../../..
<xsl:param>boost.libraries=../../../libraries.htm
<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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@ -1,33 +1,30 @@
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<div class="section" lang="en">
<div class="section" title="A note about optional&lt;bool&gt;">
<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>
@ -74,11 +70,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
</div></td>
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@ -3,108 +3,107 @@
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<div class="section" lang="en">
<div class="section" title="Acknowledgments">
<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="id2644860"></a>
<a href="acknowledgments.html#boost_optional.acknowledgments.pre_formal_review">Pre-formal
<a name="id583998"></a>
<a class="link" href="acknowledgments.html#boost_optional.acknowledgments.pre_formal_review">Pre-formal
review</a>
</h4>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
Peter Dimov suggested the name 'optional', and was the first to point out
the need for aligned storage.
</li>
<li>
<li class="listitem">
Douglas Gregor developed 'type_with_alignment', and later Eric Friedman coded
'aligned_storage', which are the core of the optional class implementation.
</li>
<li>
<li class="listitem">
Andrei Alexandrescu and Brian Parker also worked with aligned storage techniques
and their work influenced the current implementation.
</li>
<li>
<li class="listitem">
Gennadiy Rozental made extensive and important comments which shaped the
design.
</li>
<li>
<li class="listitem">
Vesa Karvonen and Douglas Gregor made quite useful comparisons between optional,
variant and any; and made other relevant comments.
</li>
<li>
<li class="listitem">
Douglas Gregor and Peter Dimov commented on comparisons and evaluation in
boolean contexts.
</li>
<li>
<li class="listitem">
Eric Friedman helped understand the issues involved with aligned storage,
move/copy operations and exception safety.
</li>
<li>
<li class="listitem">
Many others have participated with useful comments: Aleksey Gurotov, Kevlin
Henney, David Abrahams, and others I can't recall.
</li>
</ul></div>
<a name="boost_optional.acknowledgments.post_formal_review"></a><h4>
<a name="id2644931"></a>
<a href="acknowledgments.html#boost_optional.acknowledgments.post_formal_review">Post-formal
<a name="id584068"></a>
<a class="link" href="acknowledgments.html#boost_optional.acknowledgments.post_formal_review">Post-formal
review</a>
</h4>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
William Kempf carefully considered the originally proposed interface and
suggested the new interface which is currently used. He also started and
fueled the discussion about the analogy optional&lt;&gt;/smart pointer and
about relational operators.
</li>
<li>
<li class="listitem">
Peter Dimov, Joel de Guzman, David Abrahams, Tanton Gibbs and Ian Hanson
focused on the relational semantics of optional (originally undefined); concluding
with the fact that the pointer-like interface doesn't make it a pointer so
it shall have deep relational operators.
</li>
<li>
<li class="listitem">
Augustus Saunders also explored the different relational semantics between
optional&lt;&gt; and a pointer and developed the OptionalPointee concept
as an aid against potential conflicts on generic code.
</li>
<li>
<li class="listitem">
Joel de Guzman noticed that optional&lt;&gt; can be seen as an API on top
of variant&lt;T,nil_t&gt;.
</li>
<li>
<li class="listitem">
Dave Gomboc explained the meaning and usage of the Haskell analog to optional&lt;&gt;:
the Maybe type constructor (analogy originally pointed out by David Sankel).
</li>
<li>
<li class="listitem">
Other comments were posted by Vincent Finn, Anthony Williams, Ed Brey, Rob
Stewart, and others.
</li>
<li>
<li class="listitem">
Joel de Guzman made the case for the support of references and helped with
the proper semantics.
</li>
<li>
<li class="listitem">
Mat Marcus shown the virtues of a value-oriented interface, influencing the
current design, and contributed the idea of "none".
</li>
@ -112,11 +111,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
</div></td>
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and Portability">Dependencies
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and Portability</a>
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<p>
@ -36,11 +34,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
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<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<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>)
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<div class="section" lang="en">
<div class="section" title="Development">
<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>
<dt><span class="section"><a href="development.html#boost_optional.development.the_semantics">The semantics</a></span></dt>
<dt><span class="section"><a href="development.html#boost_optional.development.the_interface">The Interface</a></span></dt>
</dl></div>
<div class="section" lang="en">
<div class="section" title="The models">
<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
@ -110,28 +110,28 @@
<p>
Discriminated-union:
</p>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
<span class="bold"><strong>deep-copy</strong></span> semantics: copies of the variant
implies copies of the value.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>deep-relational</strong></span> semantics: comparisons
between variants matches both current types and values
</li>
<li>
<li class="listitem">
If the variant's current type is <code class="computeroutput"><span class="identifier">T</span></code>,
it is modeling an <span class="emphasis"><em>initialized</em></span> optional.
</li>
<li>
<li class="listitem">
If the variant's current type is not <code class="computeroutput"><span class="identifier">T</span></code>,
it is modeling an <span class="emphasis"><em>uninitialized</em></span> optional.
</li>
<li>
<li class="listitem">
Testing if the variant's current type is <code class="computeroutput"><span class="identifier">T</span></code>
models testing if the optional is initialized
</li>
<li>
<li class="listitem">
Trying to extract a <code class="computeroutput"><span class="identifier">T</span></code> from
a variant when its current type is not <code class="computeroutput"><span class="identifier">T</span></code>,
models the undefined behavior of trying to access the value of an uninitialized
@ -141,36 +141,36 @@
<p>
Single-element container:
</p>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
<span class="bold"><strong>deep-copy</strong></span> semantics: copies of the container
implies copies of the value.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>deep-relational</strong></span> semantics: comparisons
between containers compare container size and if match, contained value
</li>
<li>
<li class="listitem">
If the container is not empty (contains an object of type <code class="computeroutput"><span class="identifier">T</span></code>), it is modeling an <span class="emphasis"><em>initialized</em></span>
optional.
</li>
<li>
<li class="listitem">
If the container is empty, it is modeling an <span class="emphasis"><em>uninitialized</em></span>
optional.
</li>
<li>
<li class="listitem">
Testing if the container is empty models testing if the optional is initialized
</li>
<li>
<li class="listitem">
Trying to extract a <code class="computeroutput"><span class="identifier">T</span></code> from
an empty container models the undefined behavior of trying to access the
value of an uninitialized optional
</li>
</ul></div>
</div>
<div class="section" lang="en">
<div class="section" title="The semantics">
<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>
@ -193,55 +193,55 @@
We can draw from the purpose of <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
the required basic semantics:
</p>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
<span class="bold"><strong>Default Construction:</strong></span> To introduce a formally
uninitialized wrapped object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Direct Value Construction via copy:</strong></span> To
introduce a formally initialized wrapped object whose value is obtained
as a copy of some object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Deep Copy Construction:</strong></span> To obtain a new
yet equivalent wrapped object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Direct Value Assignment (upon initialized):</strong></span>
To assign a value to the wrapped object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Direct Value Assignment (upon uninitialized):</strong></span>
To initialize the wrapped object with a value obtained as a copy of some
object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Assignment (upon initialized):</strong></span> To assign
to the wrapped object the value of another wrapped object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Assignment (upon uninitialized):</strong></span> To initialize
the wrapped object with value of another wrapped object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Deep Relational Operations (when supported by the
type T):</strong></span> To compare wrapped object values taking into account
the presence of uninitialized states.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Value access:</strong></span> To unwrap the wrapped object.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Initialization state query:</strong></span> To determine
if the object is formally initialized or not.
</li>
<li>
<li class="listitem">
<span class="bold"><strong>Swap:</strong></span> To exchange wrapped objects. (with
whatever exception safety guarantees are provided by <code class="computeroutput"><span class="identifier">T</span></code>'s
swap).
</li>
<li>
<li class="listitem">
<span class="bold"><strong>De-initialization:</strong></span> To release the wrapped
object (if any) and leave the wrapper in the uninitialized state.
</li>
@ -252,9 +252,9 @@
via a pointer to the wrapped object or null.
</p>
</div>
<div class="section" lang="en">
<div class="section" title="The Interface">
<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="id2615242"></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="id555569"></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="id2615580"></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="id555831"></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>
@ -367,21 +367,14 @@
about the possibly uninitialized state appealing to the familiar pointer
semantics w.r.t. to null pointers.
</p>
<div class="warning"><table border="0" summary="Warning">
<div class="warning" title="Warning"><table border="0" summary="Warning">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../images/warning.png"></td>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../../../../../doc/html/images/warning.png"></td>
<th align="left">Warning</th>
</tr>
<tr><td align="left" valign="top">
<p>
</p>
<p>
However, it is particularly important to note that <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;&gt;</span></code> objects are not pointers. <span class="underline"><code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;&gt;</span></code> is not, and does not model, a
pointer</span>.
</p>
<p>
</p>
</td></tr>
<tr><td align="left" valign="top"><p>
However, it is particularly important to note that <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;&gt;</span></code> objects are not pointers. <span class="underline"><code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;&gt;</span></code> is not, and does not model, a pointer</span>.
</p></td></tr>
</table></div>
<p>
For instance, <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;&gt;</span></code>
@ -405,11 +398,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
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<div class="section" lang="en">
<div class="section" title="Examples">
<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
@ -36,14 +36,12 @@
<dt><span class="section"><a href="examples.html#boost_optional.examples.bypassing_expensive_unnecessary_default_construction">Bypassing
expensive unnecessary default construction</a></span></dt>
</dl></div>
<div class="section" lang="en">
<div class="section" title="Optional return values">
<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>
@ -59,14 +57,12 @@
<span class="special">}</span>
</pre>
</div>
<div class="section" lang="en">
<div class="section" title="Optional local variables">
<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>
@ -82,14 +78,12 @@
<span class="keyword">else</span> <span class="identifier">print</span><span class="special">(</span><span class="string">"employer's name not found!"</span><span class="special">);</span>
</pre>
</div>
<div class="section" lang="en">
<div class="section" title="Optional data members">
<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>
@ -122,14 +116,12 @@
<span class="special">};</span>
</pre>
</div>
<div class="section" lang="en">
<div class="section" title="Bypassing expensive unnecessary default construction">
<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>
@ -141,11 +133,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
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<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">
<li><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="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>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem"><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="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="special">)</span></code></li>
<li><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="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="special">)</span></code></li>
<li><code class="computeroutput"><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">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</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>
<li class="listitem"><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="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="special">)</span></code></li>
<li class="listitem"><code class="computeroutput"><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">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</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="special">)</span></code></li>
<li><code class="computeroutput"><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">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="keyword">operator</span><span class="special">=</span> <span class="special">(</span> <span class="identifier">InPlaceFactory</span>
<li class="listitem"><code class="computeroutput"><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">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</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="special">)</span></code></li>
<li><code class="computeroutput"><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">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="keyword">operator</span><span class="special">=</span> <span class="special">(</span> <span class="identifier">TypedInPlaceFactory</span>
<li class="listitem"><code class="computeroutput"><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">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</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="special">)</span> </code></li>
<li><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></code></li>
<li class="listitem"><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></code></li>
</ul></div>
<p>
Can only <span class="emphasis"><em>guarantee</em></span> the <span class="underline">basic
@ -59,9 +56,9 @@
<p>
On the other hand, the <span class="emphasis"><em>uninitializing</em></span> methods:
</p>
<div class="itemizedlist"><ul type="disc">
<li><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="keyword">operator</span><span class="special">=</span> <span class="special">(</span> <span class="identifier">detail</span><span class="special">::</span><span class="identifier">none_t</span> <span class="special">)</span></code></li>
<li><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></code></li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem"><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="keyword">operator</span><span class="special">=</span> <span class="special">(</span> <span class="identifier">detail</span><span class="special">::</span><span class="identifier">none_t</span> <span class="special">)</span></code></li>
<li class="listitem"><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></code></li>
</ul></div>
<p>
Provide the no-throw guarantee (assuming a no-throw <code class="computeroutput"><span class="identifier">T</span><span class="special">::~</span><span class="identifier">T</span><span class="special">()</span></code>)
@ -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="id2644335"></a>
<a href="exception_safety_guarantees.html#boost_optional.exception_safety_guarantees.swap">Swap</a>
<a name="id583497"></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>
@ -130,11 +126,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
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<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
@ -42,11 +41,15 @@
</div>
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<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<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>)
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<div class="section" lang="en">
<div class="section" title="In-Place Factories">
<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>
@ -127,18 +121,18 @@
<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>
The factories are divided in two groups:
</p>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
<span class="underline">TypedInPlaceFactories</span>: those which
take the target type as a primary template parameter.
</li>
<li>
<li class="listitem">
<span class="underline">InPlaceFactories</span>: those with a template
<code class="computeroutput"><span class="identifier">construct</span><span class="special">(</span><span class="keyword">void</span><span class="special">*)</span></code> member
function taking the target type.
@ -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>
@ -190,11 +182,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
</div></td>
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@ -3,29 +3,28 @@
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<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>
@ -36,20 +35,20 @@
However, since references are not real objects some restrictions apply and
some operations are not available in this case:
</p>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
Converting constructors
</li>
<li>
<li class="listitem">
Converting assignment
</li>
<li>
<li class="listitem">
InPlace construction
</li>
<li>
<li class="listitem">
InPlace assignment
</li>
<li>
<li class="listitem">
Value-access via pointer
</li>
</ul></div>
@ -58,13 +57,13 @@
treats it wrapped pseudo-object much as a real value, a true real reference
is stored so aliasing will ocurr:
</p>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
Copies of <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span></code>
will copy the references but all these references will nonetheless reefer
to the same object.
</li>
<li>
<li class="listitem">
Value-access will actually provide access to the referenced object rather
than the reference itself.
</li>
@ -72,11 +71,15 @@
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
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<div class="section" title="Rebinding semantics for assignment of optional references">
<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="id2639932"></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="id579234"></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>
@ -134,18 +128,21 @@
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>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
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</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>
@ -36,112 +35,116 @@
<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>
</div>
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<td align="left"></td>
<td align="right"><small>Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</small></td>
<td align="right"><div class="copyright-footer">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal<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>)
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In general, <code class="computeroutput"><span class="identifier">T</span></code> must be <a href="../../../../utility/CopyConstructible.html" target="_top">Copy Constructible</a> and
@ -40,11 +39,15 @@
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@ -26,8 +26,8 @@
<span class="firstname">Fernando Luis</span> <span class="surname">Cacciola Carballal</span>
</h3></div></div>
<div><p class="copyright">Copyright <20> 2003 -2007 Fernando Luis Cacciola Carballal</p></div>
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@ -38,9 +38,24 @@
<dl>
<dt><span class="section"><a href="index.html#optional.motivation">Motivation</a></span></dt>
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<dt><span class="section"><a href="boost_optional/development.html#boost_optional.development.the_models">The models</a></span></dt>
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<dt><span class="section"><a href="boost_optional/development.html#boost_optional.development.the_interface">The Interface</a></span></dt>
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@ -56,23 +71,23 @@
<dt><span class="section"><a href="boost_optional/acknowledgments.html">Acknowledgments</a></span></dt>
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<div class="section" title="Motivation">
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<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>
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<p>
Consider these functions which should return a value but which might not have
a value to return:
</p>
<div class="itemizedlist"><ul type="disc">
<li>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
(A) <code class="computeroutput"><span class="keyword">double</span> <span class="identifier">sqrt</span><span class="special">(</span><span class="keyword">double</span> <span class="identifier">n</span>
<span class="special">);</span></code>
</li>
<li>
<li class="listitem">
(B) <code class="computeroutput"><span class="keyword">char</span> <span class="identifier">get_async_input</span><span class="special">();</span></code>
</li>
<li>
<li class="listitem">
(C) <code class="computeroutput"><span class="identifier">point</span> <span class="identifier">polygon</span><span class="special">::</span><span class="identifier">get_any_point_effectively_inside</span><span class="special">();</span></code>
</li>
</ul></div>
@ -127,16 +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>
@ -151,18 +164,12 @@
</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"><small><p>Last revised: May 29, 2007 at 06:31:03 GMT</p></small></td>
<td align="right"><small></small></td>
<td align="left"><p><small>Last revised: November 20, 2009 at 10:24:28 GMT</small></p></td>
<td align="right"><div class="copyright-footer"></div></td>
</tr></table>
<hr>
<div class="spirit-nav"><a accesskey="n" href="boost_optional/development.html"><img src="images/next.png" alt="Next"></a></div>
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@ -10,8 +10,6 @@
[#optional_implementation_notes]
[section Implementation Notes]
`optional<T>` is currently implemented using a custom aligned storage facility

File diff suppressed because it is too large Load Diff

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@ -22,7 +22,7 @@ Distributed under the Boost Software License, Version 1.0.
[/ Cited Boost resources ]
[def __BOOST_VARIANT__ [@../../../variant/index.html Boost.Variant]]
[def __BOOST_TRIBOOL__ [@../../../tribool/index.html boost::tribool]]
[def __BOOST_TRIBOOL__ [@../../../../doc/html/tribool.html boost::tribool]]
[def __OPTIONAL_POINTEE__ [@../../../utility/OptionalPointee.html OptionalPointee]]
[def __COPY_CONSTRUCTIBLE__ [@../../../utility/CopyConstructible.html Copy Constructible]]
@ -40,11 +40,6 @@ Distributed under the Boost Software License, Version 1.0.
[/ Icons ]
[def __NOTE__ [$images/note.png]]
[def __ALERT__ [$images/caution.png]]
[def __DETAIL__ [$images/note.png]]
[def __TIP__ [$images/tip.png]]
[def __QUESTION_MARK__ [$images/question.png]]
[def __SPACE__ [$images/space.png]]
[def __GO_TO__ [$images/callouts/R.png]]

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@ -126,6 +126,7 @@
Because `T` might be of reference type, in the sequel, those entries whose
semantic depends on `T` being of reference type or not will be distinguished
using the following convention:
* If the entry reads: `optional<T`['(not a ref)]`>`, the description
corresponds only to the case where `T` is not of reference type.
* If the entry reads: `optional<T&>`, the description corresponds only to
@ -330,7 +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.
@ -384,7 +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 ;
@ -443,7 +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 ;

View File

@ -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& )`

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@ -4,7 +4,7 @@
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/lib/optional/ for documentation.
// See http://www.boost.org/libs/optional for documentation.
//
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
@ -20,7 +20,7 @@
namespace boost {
none_t const none = ((none_t)0) ;
none_t const none = (static_cast<none_t>(0)) ;
} // namespace boost

View File

@ -4,7 +4,7 @@
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/lib/optional for documentation.
// See http://www.boost.org/libs/optional for documentation.
//
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com

View File

@ -4,7 +4,7 @@
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/lib/optional for documentation.
// See http://www.boost.org/libs/optional for documentation.
//
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com

View File

@ -1,4 +1,4 @@
// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
// Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@ -9,6 +9,9 @@
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
//
// Revisions:
// 27 Apr 2008 (improved swap) Fernando Cacciola, Niels Dekker, Thorsten Ottosen
//
#ifndef BOOST_OPTIONAL_OPTIONAL_FLC_19NOV2002_HPP
#define BOOST_OPTIONAL_OPTIONAL_FLC_19NOV2002_HPP
@ -19,6 +22,7 @@
#include "boost/assert.hpp"
#include "boost/type.hpp"
#include "boost/type_traits/alignment_of.hpp"
#include "boost/type_traits/has_nothrow_constructor.hpp"
#include "boost/type_traits/type_with_alignment.hpp"
#include "boost/type_traits/remove_reference.hpp"
#include "boost/type_traits/is_reference.hpp"
@ -26,8 +30,9 @@
#include "boost/mpl/bool.hpp"
#include "boost/mpl/not.hpp"
#include "boost/detail/reference_content.hpp"
#include "boost/none_t.hpp"
#include "boost/none.hpp"
#include "boost/utility/compare_pointees.hpp"
#include "boost/utility/in_place_factory.hpp"
#include "boost/optional/optional_fwd.hpp"
@ -76,6 +81,19 @@
#define BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION
#endif
// Daniel Wallin discovered that bind/apply.hpp badly interacts with the apply<>
// member template of a factory as used in the optional<> implementation.
// He proposed this simple fix which is to move the call to apply<> outside
// namespace boost.
namespace boost_optional_detail
{
template <class T, class Factory>
void construct(Factory const& factory, void* address)
{
factory.BOOST_NESTED_TEMPLATE apply<T>(address);
}
}
namespace boost {
@ -173,7 +191,7 @@ class optional_base : public optional_tag
// Creates an optional<T> uninitialized.
// No-throw
optional_base ( none_t const& )
optional_base ( none_t )
:
m_initialized(false) {}
@ -266,7 +284,7 @@ class optional_base : public optional_tag
// Assigns from "none", destroying the current value, if any, leaving this UNINITIALIZED
// No-throw (assuming T::~T() doesn't)
void assign ( none_t const& ) { destroy(); }
void assign ( none_t ) { destroy(); }
#ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
template<class Expr>
@ -309,7 +327,7 @@ class optional_base : public optional_tag
void construct ( Expr const& factory, in_place_factory_base const* )
{
BOOST_STATIC_ASSERT ( ::boost::mpl::not_<is_reference_predicate>::value ) ;
factory.BOOST_NESTED_TEMPLATE apply<value_type>(m_storage.address()) ;
boost_optional_detail::construct<value_type>(factory, m_storage.address());
m_initialized = true ;
}
@ -428,6 +446,8 @@ class optional_base : public optional_tag
// the following olverloads are used to filter out the case and guarantee an error in case of T being a reference.
pointer_const_type cast_ptr( internal_type const* p, is_not_reference_tag ) const { return p ; }
pointer_type cast_ptr( internal_type * p, is_not_reference_tag ) { return p ; }
pointer_const_type cast_ptr( internal_type const* p, is_reference_tag ) const { return &p->get() ; }
pointer_type cast_ptr( internal_type * p, is_reference_tag ) { return &p->get() ; }
bool m_initialized ;
storage_type m_storage ;
@ -459,7 +479,7 @@ class optional : public optional_detail::optional_base<T>
// Creates an optional<T> uninitialized.
// No-throw
optional( none_t const& none_ ) : base(none_) {}
optional( none_t none_ ) : base(none_) {}
// Creates an optional<T> initialized with 'val'.
// Can throw if T::T(T const&) does
@ -501,7 +521,7 @@ class optional : public optional_detail::optional_base<T>
// Creates a deep copy of another optional<T>
// Can throw if T::T(T const&) does
optional ( optional const& rhs ) : base(rhs) {}
optional ( optional const& rhs ) : base( static_cast<base const&>(rhs) ) {}
// No-throw (assuming T::~T() doesn't)
~optional() {}
@ -535,7 +555,7 @@ class optional : public optional_detail::optional_base<T>
// (NOTE: On BCB, this operator is not actually called and left is left UNMODIFIED in case of a throw)
optional& operator= ( optional const& rhs )
{
this->assign( rhs ) ;
this->assign( static_cast<base const&>(rhs) ) ;
return *this ;
}
@ -550,12 +570,20 @@ class optional : public optional_detail::optional_base<T>
// Assigns from a "none"
// Which destroys the current value, if any, leaving this UNINITIALIZED
// No-throw (assuming T::~T() doesn't)
optional& operator= ( none_t const& none_ )
optional& operator= ( none_t none_ )
{
this->assign( none_ ) ;
return *this ;
}
void swap( optional & arg )
{
// allow for Koenig lookup
using boost::swap ;
swap(*this, arg);
}
// Returns a reference to the value if this is initialized, otherwise,
// the behaviour is UNDEFINED
// No-throw
@ -678,6 +706,11 @@ get_pointer ( optional<T>& opt )
// optional's relational operators ( ==, !=, <, >, <=, >= ) have deep-semantics (compare values).
// WARNING: This is UNLIKE pointers. Use equal_pointees()/less_pointess() in generic code instead.
//
// optional<T> vs optional<T> cases
//
template<class T>
inline
bool operator == ( optional<T> const& x, optional<T> const& y )
@ -708,64 +741,141 @@ inline
bool operator >= ( optional<T> const& x, optional<T> const& y )
{ return !( x < y ) ; }
//
// optional<T> vs T cases
//
template<class T>
inline
bool operator == ( optional<T> const& x, none_t const& )
bool operator == ( optional<T> const& x, T const& y )
{ return equal_pointees(x, optional<T>(y)); }
template<class T>
inline
bool operator < ( optional<T> const& x, T const& y )
{ return less_pointees(x, optional<T>(y)); }
template<class T>
inline
bool operator != ( optional<T> const& x, T const& y )
{ return !( x == y ) ; }
template<class T>
inline
bool operator > ( optional<T> const& x, T const& y )
{ return y < x ; }
template<class T>
inline
bool operator <= ( optional<T> const& x, T const& y )
{ return !( y < x ) ; }
template<class T>
inline
bool operator >= ( optional<T> const& x, T const& y )
{ return !( x < y ) ; }
//
// T vs optional<T> cases
//
template<class T>
inline
bool operator == ( T const& x, optional<T> const& y )
{ return equal_pointees( optional<T>(x), y ); }
template<class T>
inline
bool operator < ( T const& x, optional<T> const& y )
{ return less_pointees( optional<T>(x), y ); }
template<class T>
inline
bool operator != ( T const& x, optional<T> const& y )
{ return !( x == y ) ; }
template<class T>
inline
bool operator > ( T const& x, optional<T> const& y )
{ return y < x ; }
template<class T>
inline
bool operator <= ( T const& x, optional<T> const& y )
{ return !( y < x ) ; }
template<class T>
inline
bool operator >= ( T const& x, optional<T> const& y )
{ return !( x < y ) ; }
//
// optional<T> vs none cases
//
template<class T>
inline
bool operator == ( optional<T> const& x, none_t )
{ return equal_pointees(x, optional<T>() ); }
template<class T>
inline
bool operator < ( optional<T> const& x, none_t const& )
bool operator < ( optional<T> const& x, none_t )
{ return less_pointees(x,optional<T>() ); }
template<class T>
inline
bool operator != ( optional<T> const& x, none_t const& y )
bool operator != ( optional<T> const& x, none_t y )
{ return !( x == y ) ; }
template<class T>
inline
bool operator > ( optional<T> const& x, none_t const& y )
bool operator > ( optional<T> const& x, none_t y )
{ return y < x ; }
template<class T>
inline
bool operator <= ( optional<T> const& x, none_t const& y )
bool operator <= ( optional<T> const& x, none_t y )
{ return !( y < x ) ; }
template<class T>
inline
bool operator >= ( optional<T> const& x, none_t const& y )
bool operator >= ( optional<T> const& x, none_t y )
{ return !( x < y ) ; }
//
// none vs optional<T> cases
//
template<class T>
inline
bool operator == ( none_t const& x, optional<T> const& y )
bool operator == ( none_t x, optional<T> const& y )
{ return equal_pointees(optional<T>() ,y); }
template<class T>
inline
bool operator < ( none_t const& x, optional<T> const& y )
bool operator < ( none_t x, optional<T> const& y )
{ return less_pointees(optional<T>() ,y); }
template<class T>
inline
bool operator != ( none_t const& x, optional<T> const& y )
bool operator != ( none_t x, optional<T> const& y )
{ return !( x == y ) ; }
template<class T>
inline
bool operator > ( none_t const& x, optional<T> const& y )
bool operator > ( none_t x, optional<T> const& y )
{ return y < x ; }
template<class T>
inline
bool operator <= ( none_t const& x, optional<T> const& y )
bool operator <= ( none_t x, optional<T> const& y )
{ return !( y < x ) ; }
template<class T>
inline
bool operator >= ( none_t const& x, optional<T> const& y )
bool operator >= ( none_t x, optional<T> const& y )
{ return !( x < y ) ; }
//
@ -781,44 +891,77 @@ namespace optional_detail {
#define BOOST_OPTIONAL_STD_SWAP_INTRODUCED_AT_NS_SCOPE
#endif
// optional's swap:
// If both are initialized, calls swap(T&, T&). If this swap throws, both will remain initialized but their values are now unspecified.
// If only one is initialized, calls U.reset(*I), THEN I.reset().
// If U.reset(*I) throws, both are left UNCHANGED (U is kept uinitialized and I is never reset)
// If both are uninitialized, do nothing (no-throw)
template<class T>
inline
void optional_swap ( optional<T>& x, optional<T>& y )
{
if ( !x && !!y )
template<bool use_default_constructor> struct swap_selector;
template<>
struct swap_selector<true>
{
x.reset(*y);
y.reset();
}
else if ( !!x && !y )
{
y.reset(*x);
x.reset();
}
else if ( !!x && !!y )
{
// GCC > 3.2 and all other compilers have the using declaration at function scope (FLC)
template<class T>
static void optional_swap ( optional<T>& x, optional<T>& y )
{
bool hasX = x;
bool hasY = y;
if ( !hasX && !hasY )
return;
if( !hasX )
x = boost::in_place();
else if ( !hasY )
y = boost::in_place();
// GCC > 3.2 and all other compilers have the using declaration at function scope (FLC)
#ifndef BOOST_OPTIONAL_STD_SWAP_INTRODUCED_AT_NS_SCOPE
// allow for Koenig lookup
using std::swap ;
// allow for Koenig lookup
using std::swap ;
#endif
swap(*x,*y);
}
}
swap(*x,*y);
if( !hasX )
y = boost::none ;
else if( !hasY )
x = boost::none ;
}
};
template<>
struct swap_selector<false>
{
template<class T>
static void optional_swap ( optional<T>& x, optional<T>& y )
{
if ( !x && !!y )
{
x = *y;
y = boost::none ;
}
else if ( !!x && !y )
{
y = *x ;
x = boost::none ;
}
else if ( !!x && !!y )
{
// GCC > 3.2 and all other compilers have the using declaration at function scope (FLC)
#ifndef BOOST_OPTIONAL_STD_SWAP_INTRODUCED_AT_NS_SCOPE
// allow for Koenig lookup
using std::swap ;
#endif
swap(*x,*y);
}
}
};
} // namespace optional_detail
template<class T>
struct optional_swap_should_use_default_constructor : has_nothrow_default_constructor<T> {} ;
template<class T> inline void swap ( optional<T>& x, optional<T>& y )
{
optional_detail::optional_swap(x,y);
optional_detail::swap_selector<optional_swap_should_use_default_constructor<T>::value>::optional_swap(x, y);
}
} // namespace boost
#endif

View File

@ -1,4 +1,4 @@
// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
// Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@ -9,6 +9,9 @@
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
//
// Revisions:
// 10 May 2008 (added swap related forward declaration) Niels Dekker
//
#ifndef BOOST_OPTIONAL_OPTIONAL_FWD_FLC_19NOV2002_HPP
#define BOOST_OPTIONAL_OPTIONAL_FWD_FLC_19NOV2002_HPP
@ -16,6 +19,10 @@ namespace boost {
template<class T> class optional ;
template<class T> void swap ( optional<T>& , optional<T>& ) ;
template<class T> struct optional_swap_should_use_default_constructor ;
} // namespace boost
#endif

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@ -1,13 +1,13 @@
<html>
<head>
<meta http-equiv="refresh" content="0; URL=doc/optional.html">
<meta http-equiv="refresh" content="0; URL=doc/html/index.html">
</head>
<body>
Automatic redirection failed, please go to
<a href="doc/optional.html">doc/optional.html</a>.&nbsp;<hr>
<p><EFBFBD> Copyright Beman Dawes, 2001</p>
<a href="doc/html/index.html">doc/html/index.html</a>.&nbsp;<hr>
<p><EFBFBD> Copyright Beman Dawes, 2001</p>
<p>Distributed under the Boost Software License, Version 1.0. (See accompanying
file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or copy
at <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</p>
</body>
</html>
</html>

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@ -1 +0,0 @@
bin

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@ -22,11 +22,9 @@ import testing ;
[ run optional_test_inplace.cpp ]
[ run optional_test_io.cpp ]
[ compile-fail optional_test_fail1.cpp ]
[ compile-fail optional_test_fail2.cpp ]
[ compile-fail optional_test_fail3a.cpp ]
[ compile-fail optional_test_fail3b.cpp ]
[ compile-fail optional_test_ref_fail1.cpp ]
[ compile-fail optional_test_ref_fail2.cpp ]
[ compile-fail optional_test_ref_fail3.cpp ]
[ compile-fail optional_test_ref_fail4.cpp ]
[ compile-fail optional_test_inplace_fail.cpp ]

View File

@ -1,4 +1,4 @@
// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
// Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@ -9,6 +9,9 @@
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
//
// Revisions:
// 12 May 2008 (added more swap tests)
//
#include<iostream>
#include<stdexcept>
#include<string>
@ -16,6 +19,8 @@
#define BOOST_ENABLE_ASSERT_HANDLER
#include "boost/bind/apply.hpp" // Included just to test proper interaction with boost::apply<> as reported by Daniel Wallin
#include "boost/mpl/bool.hpp"
#include "boost/mpl/bool_fwd.hpp" // For mpl::true_ and mpl::false_
#include "boost/optional/optional.hpp"
@ -704,16 +709,16 @@ void test_relops( T const* )
{
TRACE( std::endl << BOOST_CURRENT_FUNCTION );
T v0(18);
T v1(19);
T v2(19);
T v0(0);
T v1(1);
T v2(1);
optional<T> def0 ;
optional<T> def1 ;
optional<T> opt0(v0);
optional<T> opt1(v1);
optional<T> opt2(v2);
// Check identity
BOOST_CHECK ( def0 == def0 ) ;
BOOST_CHECK ( opt0 == opt0 ) ;
@ -751,6 +756,33 @@ void test_relops( T const* )
BOOST_CHECK ( opt1 > opt0 ) ;
BOOST_CHECK ( opt1 <= opt2 ) ;
BOOST_CHECK ( opt1 >= opt0 ) ;
// Compare against a value directly
BOOST_CHECK ( opt0 == v0 ) ;
BOOST_CHECK ( opt0 != v1 ) ;
BOOST_CHECK ( opt1 == v2 ) ;
BOOST_CHECK ( opt0 < v1 ) ;
BOOST_CHECK ( opt1 > v0 ) ;
BOOST_CHECK ( opt1 <= v2 ) ;
BOOST_CHECK ( opt1 >= v0 ) ;
BOOST_CHECK ( v0 != opt1 ) ;
BOOST_CHECK ( v1 == opt2 ) ;
BOOST_CHECK ( v0 < opt1 ) ;
BOOST_CHECK ( v1 > opt0 ) ;
BOOST_CHECK ( v1 <= opt2 ) ;
BOOST_CHECK ( v1 >= opt0 ) ;
BOOST_CHECK ( def0 != v0 ) ;
BOOST_CHECK ( !(def0 == v0) ) ;
BOOST_CHECK ( def0 < v0 ) ;
BOOST_CHECK ( !(def0 > v0) ) ;
BOOST_CHECK ( def0 <= v0 ) ;
BOOST_CHECK ( !(def0 >= v0) ) ;
BOOST_CHECK ( v0 != def0 ) ;
BOOST_CHECK ( !(v0 == def0) ) ;
BOOST_CHECK ( !(v0 < def0) ) ;
BOOST_CHECK ( v0 > def0 ) ;
BOOST_CHECK ( !(v0 <= def0) ) ;
BOOST_CHECK ( v0 >= opt0 ) ;
}
template<class T>
@ -767,6 +799,10 @@ void test_none( T const* )
BOOST_CHECK ( def0 == none ) ;
BOOST_CHECK ( non_def != none ) ;
BOOST_CHECK ( !def1 ) ;
BOOST_CHECK ( !(non_def < none) ) ;
BOOST_CHECK ( non_def > none ) ;
BOOST_CHECK ( !(non_def <= none) ) ;
BOOST_CHECK ( non_def >= none ) ;
non_def = none ;
BOOST_CHECK ( !non_def ) ;
@ -774,6 +810,24 @@ void test_none( T const* )
test_default_implicit_construction(T(1),none);
}
template<class T>
void test_arrow( T const* )
{
TRACE( std::endl << BOOST_CURRENT_FUNCTION );
T a(1234);
optional<T> oa(a) ;
optional<T> const coa(a) ;
BOOST_CHECK ( coa->V() == 1234 ) ;
oa->V() = 4321 ;
BOOST_CHECK ( a.V() = 1234 ) ;
BOOST_CHECK ( (*oa).V() = 4321 ) ;
}
void test_with_builtin_types()
{
TRACE( std::endl << BOOST_CURRENT_FUNCTION );
@ -804,6 +858,7 @@ void test_with_class_type()
test_throwing_swap( ARG(X) );
test_relops( ARG(X) ) ;
test_none( ARG(X) ) ;
test_arrow( ARG(X) ) ;
BOOST_CHECK ( X::count == 0 ) ;
}
@ -877,6 +932,337 @@ void test_conversions2()
BOOST_CHECK(*get(&opt1) == static_cast<double>(f));
}
namespace optional_swap_test
{
class default_ctor_exception : public std::exception {} ;
class copy_ctor_exception : public std::exception {} ;
class assignment_exception : public std::exception {} ;
//
// Base class for swap test classes. Its assignment should not be called, when swapping
// optional<T> objects. (The default std::swap would do so.)
//
class base_class_with_forbidden_assignment
{
public:
base_class_with_forbidden_assignment & operator=(const base_class_with_forbidden_assignment &)
{
BOOST_CHECK(!"The assignment should not be used while swapping!");
throw assignment_exception();
}
virtual ~base_class_with_forbidden_assignment() {}
};
//
// Class without default constructor
//
class class_without_default_ctor : public base_class_with_forbidden_assignment
{
public:
char data;
explicit class_without_default_ctor(char arg) : data(arg) {}
};
//
// Class whose default constructor should not be used by optional::swap!
//
class class_whose_default_ctor_should_not_be_used : public base_class_with_forbidden_assignment
{
public:
char data;
explicit class_whose_default_ctor_should_not_be_used(char arg) : data(arg) {}
class_whose_default_ctor_should_not_be_used()
{
BOOST_CHECK(!"This default constructor should not be used while swapping!");
throw default_ctor_exception();
}
};
//
// Class whose default constructor should be used by optional::swap.
// Its copy constructor should be avoided!
//
class class_whose_default_ctor_should_be_used : public base_class_with_forbidden_assignment
{
public:
char data;
explicit class_whose_default_ctor_should_be_used(char arg) : data(arg) { }
class_whose_default_ctor_should_be_used() : data('\0') { }
class_whose_default_ctor_should_be_used(const class_whose_default_ctor_should_be_used &)
{
BOOST_CHECK(!"This copy constructor should not be used while swapping!");
throw copy_ctor_exception();
}
};
//
// Class template whose default constructor should be used by optional::swap.
// Its copy constructor should be avoided!
//
template <class T>
class template_whose_default_ctor_should_be_used : public base_class_with_forbidden_assignment
{
public:
T data;
explicit template_whose_default_ctor_should_be_used(T arg) : data(arg) { }
template_whose_default_ctor_should_be_used() : data('\0') { }
template_whose_default_ctor_should_be_used(const template_whose_default_ctor_should_be_used &)
{
BOOST_CHECK(!"This copy constructor should not be used while swapping!");
throw copy_ctor_exception();
}
};
//
// Class whose explicit constructor should be used by optional::swap.
// Its other constructors should be avoided!
//
class class_whose_explicit_ctor_should_be_used : public base_class_with_forbidden_assignment
{
public:
char data;
explicit class_whose_explicit_ctor_should_be_used(char arg) : data(arg) { }
class_whose_explicit_ctor_should_be_used()
{
BOOST_CHECK(!"This default constructor should not be used while swapping!");
throw default_ctor_exception();
}
class_whose_explicit_ctor_should_be_used(const class_whose_explicit_ctor_should_be_used &)
{
BOOST_CHECK(!"This copy constructor should not be used while swapping!");
throw copy_ctor_exception();
}
};
void swap(class_whose_default_ctor_should_not_be_used & lhs, class_whose_default_ctor_should_not_be_used & rhs)
{
std::swap(lhs.data, rhs.data);
}
void swap(class_whose_default_ctor_should_be_used & lhs, class_whose_default_ctor_should_be_used & rhs)
{
std::swap(lhs.data, rhs.data);
}
void swap(class_without_default_ctor & lhs, class_without_default_ctor & rhs)
{
std::swap(lhs.data, rhs.data);
}
void swap(class_whose_explicit_ctor_should_be_used & lhs, class_whose_explicit_ctor_should_be_used & rhs)
{
std::swap(lhs.data, rhs.data);
}
template <class T>
void swap(template_whose_default_ctor_should_be_used<T> & lhs, template_whose_default_ctor_should_be_used<T> & rhs)
{
std::swap(lhs.data, rhs.data);
}
//
// optional<T>::swap should be customized when neither the copy constructor
// nor the default constructor of T are supposed to be used when swapping, e.g.,
// for the following type T = class_whose_explicit_ctor_should_be_used.
//
void swap(boost::optional<class_whose_explicit_ctor_should_be_used> & x, boost::optional<class_whose_explicit_ctor_should_be_used> & y)
{
bool hasX = x;
bool hasY = y;
if ( !hasX && !hasY )
return;
if( !hasX )
x = boost::in_place('\0');
else if ( !hasY )
y = boost::in_place('\0');
optional_swap_test::swap(*x,*y);
if( !hasX )
y = boost::none ;
else if( !hasY )
x = boost::none ;
}
} // End of namespace optional_swap_test.
namespace boost {
//
// Compile time tweaking on whether or not swap should use the default constructor:
//
template <> struct optional_swap_should_use_default_constructor<
optional_swap_test::class_whose_default_ctor_should_be_used> : mpl::true_ {} ;
template <> struct optional_swap_should_use_default_constructor<
optional_swap_test::class_whose_default_ctor_should_not_be_used> : mpl::false_ {} ;
template <class T> struct optional_swap_should_use_default_constructor<
optional_swap_test::template_whose_default_ctor_should_be_used<T> > : mpl::true_ {} ;
//
// Specialization of boost::swap:
//
template <>
void swap(optional<optional_swap_test::class_whose_explicit_ctor_should_be_used> & x, optional<optional_swap_test::class_whose_explicit_ctor_should_be_used> & y)
{
optional_swap_test::swap(x, y);
}
} // namespace boost
namespace std {
//
// Specializations of std::swap:
//
template <>
void swap(optional_swap_test::class_whose_default_ctor_should_be_used & x, optional_swap_test::class_whose_default_ctor_should_be_used & y)
{
optional_swap_test::swap(x, y);
}
template <>
void swap(optional_swap_test::class_whose_default_ctor_should_not_be_used & x, optional_swap_test::class_whose_default_ctor_should_not_be_used & y)
{
optional_swap_test::swap(x, y);
}
template <>
void swap(optional_swap_test::class_without_default_ctor & x, optional_swap_test::class_without_default_ctor & y)
{
optional_swap_test::swap(x, y);
}
template <>
void swap(optional_swap_test::class_whose_explicit_ctor_should_be_used & x, optional_swap_test::class_whose_explicit_ctor_should_be_used & y)
{
optional_swap_test::swap(x, y);
}
} // namespace std
//
// Tests whether the swap function works properly for optional<T>.
// Assumes that T has one data member, of type char.
// Returns true iff the test is passed.
//
template <class T>
bool test_swap_function( T const* )
{
const boost::unit_test::counter_t counter_before_test = boost::minimal_test::errors_counter();
try
{
optional<T> obj1;
optional<T> obj2('a');
// Self-swap should not have any effect.
swap(obj1, obj1);
swap(obj2, obj2);
BOOST_CHECK(!obj1);
BOOST_CHECK(!!obj2 && obj2->data == 'a');
// Call non-member swap.
swap(obj1, obj2);
// Test if obj1 and obj2 are really swapped.
BOOST_CHECK(!!obj1 && obj1->data == 'a');
BOOST_CHECK(!obj2);
// Call non-member swap one more time.
swap(obj1, obj2);
// Test if obj1 and obj2 are swapped back.
BOOST_CHECK(!obj1);
BOOST_CHECK(!!obj2 && obj2->data == 'a');
}
catch(const std::exception &)
{
// The swap function should not throw, for our test cases.
return false ;
}
return boost::minimal_test::errors_counter() == counter_before_test ;
}
//
// Tests whether the optional<T>::swap member function works properly.
// Assumes that T has one data member, of type char.
// Returns true iff the test is passed.
//
template <class T>
bool test_swap_member_function( T const* )
{
const boost::unit_test::counter_t counter_before_test = boost::minimal_test::errors_counter();
try
{
optional<T> obj1;
optional<T> obj2('a');
// Self-swap should not have any effect.
obj1.swap(obj1);
obj2.swap(obj2);
BOOST_CHECK(!obj1);
BOOST_CHECK(!!obj2 && obj2->data == 'a');
// Call member swap.
obj1.swap(obj2);
// Test if obj1 and obj2 are really swapped.
BOOST_CHECK(!!obj1 && obj1->data == 'a');
BOOST_CHECK(!obj2);
// Call member swap one more time.
obj1.swap(obj2);
// Test if obj1 and obj2 are swapped back.
BOOST_CHECK(!obj1);
BOOST_CHECK(!!obj2 && obj2->data == 'a');
}
catch(const std::exception &)
{
// The optional<T>::swap member function should not throw, for our test cases.
return false ;
}
return boost::minimal_test::errors_counter() == counter_before_test ;
}
//
// Tests compile time tweaking of swap, by means of
// optional_swap_should_use_default_constructor.
//
void test_swap_tweaking()
{
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::class_without_default_ctor) ) );
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::class_whose_default_ctor_should_be_used) ) );
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::class_whose_default_ctor_should_not_be_used) ) );
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::class_whose_explicit_ctor_should_be_used) ) );
BOOST_CHECK( test_swap_function( ARG(optional_swap_test::template_whose_default_ctor_should_be_used<char>) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::class_without_default_ctor) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::class_whose_default_ctor_should_be_used) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::class_whose_default_ctor_should_not_be_used) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::class_whose_explicit_ctor_should_be_used) ) );
BOOST_CHECK( test_swap_member_function( ARG(optional_swap_test::template_whose_default_ctor_should_be_used<char>) ) );
}
int test_main( int, char* [] )
{
try
@ -886,6 +1272,7 @@ int test_main( int, char* [] )
test_no_implicit_conversions();
test_conversions1();
test_conversions2();
test_swap_tweaking();
}
catch ( ... )
{

View File

@ -299,6 +299,23 @@ void test_none( T const* )
BOOST_CHECK ( !non_def ) ;
}
template<class T>
void test_arrow( T const* )
{
TRACE( std::endl << BOOST_CURRENT_FUNCTION );
T a(1234);
optional<T&> oa(a) ;
optional<T&> const coa(a) ;
BOOST_CHECK ( coa->V() == 1234 ) ;
oa->V() = 4321 ;
BOOST_CHECK ( a.V() = 4321 ) ;
}
void test_with_builtin_types()
{
TRACE( std::endl << BOOST_CURRENT_FUNCTION );
@ -315,16 +332,35 @@ void test_with_class_type()
test_basics( ARG(X) );
test_relops( ARG(X) ) ;
test_none ( ARG(X) ) ;
test_arrow ( ARG(X) ) ;
BOOST_CHECK ( X::count == 0 ) ;
}
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 ) ;
}
int test_main( int, char* [] )
{
try
{
test_with_class_type();
test_with_builtin_types();
test_binding();
}
catch ( ... )
{

View File

@ -1,23 +0,0 @@
// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/lib/optional for documentation.
//
// You are welcome to contact the author at:
// fernando_cacciola@hotmail.com
//
#include "boost/optional.hpp"
//
// THIS TEST SHOULD FAIL TO COMPILE
//
void optional_reference__test_no_ptr_access()
{
boost::optional<int&> opt ;
opt.get_ptr();
}