forked from boostorg/fusion
Eric Niebler
798b2f4017
https://svn.boost.org/svn/boost/trunk ........ r41077 | troyer | 2007-11-13 23:00:02 -0800 (Tue, 13 Nov 2007) | 1 line Added support for std::complex to serialization ........ r41078 | joaquin | 2007-11-13 23:09:29 -0800 (Tue, 13 Nov 2007) | 1 line added missing include ........ r41079 | djowel | 2007-11-14 02:13:51 -0800 (Wed, 14 Nov 2007) | 1 line adjust to compensate for lack of <small> tag. ........ r41080 | djowel | 2007-11-14 02:17:09 -0800 (Wed, 14 Nov 2007) | 1 line refresh docs ........ r41081 | djowel | 2007-11-14 02:23:23 -0800 (Wed, 14 Nov 2007) | 1 line refresh docs ........ r41082 | djowel | 2007-11-14 02:24:21 -0800 (Wed, 14 Nov 2007) | 1 line refresh docs ........ r41083 | anthonyw | 2007-11-14 03:08:09 -0800 (Wed, 14 Nov 2007) | 1 line ignore and join all threads in group on exception ........ r41084 | anthonyw | 2007-11-14 03:56:53 -0800 (Wed, 14 Nov 2007) | 1 line interrupt and join all threads in a group if an exception is thrown during a test ........ r41086 | johnmaddock | 2007-11-14 04:14:19 -0800 (Wed, 14 Nov 2007) | 1 line Merged changes from the Sandbox to Trunk. ........ r41087 | anthonyw | 2007-11-14 04:17:41 -0800 (Wed, 14 Nov 2007) | 1 line interrupt and join all threads in a group if an exception is thrown during a test ........ r41088 | johnmaddock | 2007-11-14 04:41:32 -0800 (Wed, 14 Nov 2007) | 1 line Added WinCE workaround. ........ r41089 | johnmaddock | 2007-11-14 05:03:15 -0800 (Wed, 14 Nov 2007) | 1 line Catch exceptions thrown from thread creation. ........ r41090 | anthonyw | 2007-11-14 06:49:58 -0800 (Wed, 14 Nov 2007) | 1 line fixes for pthread implementation ........ r41091 | bemandawes | 2007-11-14 07:50:43 -0800 (Wed, 14 Nov 2007) | 1 line Replace old docs with excerpts from http://article.gmane.org/gmane.comp.lib.boost.testing/5020 ........ r41093 | eric_niebler | 2007-11-14 08:36:15 -0800 (Wed, 14 Nov 2007) | 1 line fix support for segmented iteration ........ r41094 | dave | 2007-11-14 09:37:55 -0800 (Wed, 14 Nov 2007) | 3 lines Update command-prompt instructions per http://news.gmane.org/find-root.php?message_id=%3cfhcrem%24c4%241%40ger.gmane.org%3e ........ r41095 | bemandawes | 2007-11-14 12:05:30 -0800 (Wed, 14 Nov 2007) | 1 line Bring docs more in line with reality:-) ........ r41097 | hljin | 2007-11-14 18:07:53 -0800 (Wed, 14 Nov 2007) | 1 line GIL: removed the example directory from the documentation as it is a duplication and re-directed the Doxygen documentation to a local copy (to be submitted next) ........ r41098 | hljin | 2007-11-14 18:30:13 -0800 (Wed, 14 Nov 2007) | 1 line GIL: added a local copy of the Doxygen documentation ........ r41099 | hljin | 2007-11-14 18:32:04 -0800 (Wed, 14 Nov 2007) | 1 line GIL: added a local copy of the Doxygen documentation (second batch) ........ r41100 | chris_kohlhoff | 2007-11-14 22:19:04 -0800 (Wed, 14 Nov 2007) | 6 lines Try to fix an order-of-initialisation problem with error_category references. The symptom, which only occurs in some applications, is a crash due to a dereference of a null pointer. The exact conditions under which the problem occurs are not fully understood, so this fix is probably more paranoid than necessary. ........ r41102 | jhunold | 2007-11-14 23:04:24 -0800 (Wed, 14 Nov 2007) | 1 line Suppress msvc "deprecated" warnings. ........ r41103 | johnmaddock | 2007-11-15 01:52:26 -0800 (Thu, 15 Nov 2007) | 1 line Fix some compiler warnings when building with the Intel and aCC compilers. ........ r41104 | garcia | 2007-11-15 04:50:48 -0800 (Thu, 15 Nov 2007) | 2 lines John Torjo is reviewing the X-files. ........ r41105 | hkaiser | 2007-11-15 05:27:24 -0800 (Thu, 15 Nov 2007) | 1 line Suppressed more warnings during build of Wave. ........ r41106 | bemandawes | 2007-11-15 06:36:40 -0800 (Thu, 15 Nov 2007) | 1 line GetUserDefaultUILanguage isn't present for Cygwin, so disable use ........ r41107 | bemandawes | 2007-11-15 07:20:27 -0800 (Thu, 15 Nov 2007) | 1 line Get rid of .cvsignore files ........ r41108 | eric_niebler | 2007-11-15 08:06:22 -0800 (Thu, 15 Nov 2007) | 1 line fix typo ........ r41110 | grafik | 2007-11-15 08:58:21 -0800 (Thu, 15 Nov 2007) | 1 line Fix building of multiple regression tools at once. ........ r41111 | gmelquio | 2007-11-15 09:52:31 -0800 (Thu, 15 Nov 2007) | 1 line Fixed documentation typo. ........ r41113 | grafik | 2007-11-15 10:56:43 -0800 (Thu, 15 Nov 2007) | 1 line Switch intel-win32 to use static multi thread runtime since the single thread static runtime is no longer available. (fixes #1287) ........ r41114 | andreas_huber69 | 2007-11-15 11:22:12 -0800 (Thu, 15 Nov 2007) | 1 line Added new FAQ item suggested by Chris Paulse. ........ r41116 | guwi17 | 2007-11-15 12:52:37 -0800 (Thu, 15 Nov 2007) | 4 lines This patch now lets the Sun compiler work for most of uBLAS. 'test4' is now failing. Too avoid other compilers complaining about missing return values in some functions where exceptions are thrown, code was added so an arbitatry were chosen. ........ r41117 | danmarsden | 2007-11-15 13:15:47 -0800 (Thu, 15 Nov 2007) | 1 line removing failing test on EDG compilers ........ r41118 | grafik | 2007-11-15 14:05:15 -0800 (Thu, 15 Nov 2007) | 1 line Remove redundant reference to system library. It causes double linking when used indirectly through filesystem. Which can lead to double linking incompatible variants when a specific filesystem variant is requested. ........ r41119 | grafik | 2007-11-15 14:05:22 -0800 (Thu, 15 Nov 2007) | 1 line Oops, forgot we need to use the root boost project settings when building. ........ [SVN r41141]
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268 lines
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<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
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<link rel="start" href="../index.html" title="Chapter 1. Fusion 2.0">
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<a accesskey="p" href="introduction.html"><img src="../../../../../doc/html/images/prev.png" alt="Prev"></a><a accesskey="u" href="../index.html"><img src="../../../../../doc/html/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../doc/html/images/home.png" alt="Home"></a><a accesskey="n" href="organization.html"><img src="../../../../../doc/html/images/next.png" alt="Next"></a>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
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<a name="fusion.quick_start"></a><a href="quick_start.html" title="Quick Start">Quick Start</a></h2></div></div></div>
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<p>
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I assume the reader is already familiar with tuples (<a href="http://www.boost.org/libs/tuple/doc/tuple_users_guide.html" target="_top">Boost.Tuple</a>)
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and its ancestor <tt class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></tt>. The tuple is a generalization of <tt class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></tt>
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for multiple heterogeneous elements (triples, quadruples, etc.). The tuple
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is more or less a synonym for fusion's <tt class="computeroutput"><a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a></tt>.
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</p>
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<p>
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For starters, we shall include all of Fusion's <a href="sequence.html" title="Sequence">Sequence</a>(s)
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<sup>[<a name="id456266" href="#ftn.id456266">1</a>]</sup>
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:
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</p>
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<pre class="programlisting">
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<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">sequence</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
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<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">sequence</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
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</pre>
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<p>
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Let's begin with a <tt class="computeroutput"><a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a></tt>
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<sup>[<a name="id456433" href="#ftn.id456433">2</a>]</sup>
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:
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</p>
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<pre class="programlisting">
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<a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a><span class="special"><</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">char</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">></span> <span class="identifier">stuff</span><span class="special">(</span><span class="number">1</span><span class="special">,</span> <span class="char">'x'</span><span class="special">,</span> <span class="string">"howdy"</span><span class="special">);</span>
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<span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <a href="sequence/intrinsic/functions/at_c.html" title="at_c"><tt class="computeroutput"><span class="identifier">at_c</span></tt></a><span class="special"><</span><span class="number">0</span><span class="special">>(</span><span class="identifier">stuff</span><span class="special">);</span>
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<span class="keyword">char</span> <span class="identifier">ch</span> <span class="special">=</span> <a href="sequence/intrinsic/functions/at_c.html" title="at_c"><tt class="computeroutput"><span class="identifier">at_c</span></tt></a><span class="special"><</span><span class="number">1</span><span class="special">>(</span><span class="identifier">stuff</span><span class="special">);</span>
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<span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span> <span class="special">=</span> <a href="sequence/intrinsic/functions/at_c.html" title="at_c"><tt class="computeroutput"><span class="identifier">at_c</span></tt></a><span class="special"><</span><span class="number">2</span><span class="special">>(</span><span class="identifier">stuff</span><span class="special">);</span>
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</pre>
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<p>
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Just replace <tt class="computeroutput"><span class="identifier">tuple</span></tt> for <tt class="computeroutput"><a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a></tt>
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and <tt class="computeroutput"><span class="identifier">get</span></tt> for <tt class="computeroutput"><a href="sequence/intrinsic/functions/at_c.html" title="at_c"><tt class="computeroutput"><span class="identifier">at_c</span></tt></a></tt> and this is exactly like
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<a href="http://www.boost.org/libs/tuple/doc/tuple_users_guide.html" target="_top">Boost.Tuple</a>.
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Actually, either names can be used interchangeably. Yet, the similarity ends
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there. You can do a lot more with Fusion <tt class="computeroutput"><a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a></tt> or <tt class="computeroutput"><span class="identifier">tuple</span></tt>.
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Let's see some examples.
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</p>
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<a name="fusion.quick_start.print_the_vector_as_xml"></a><h3>
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<a name="id456896"></a>
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<a href="quick_start.html#fusion.quick_start.print_the_vector_as_xml">Print the vector
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as XML</a>
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</h3>
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<p>
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First, let's include the algorithms:
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</p>
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<pre class="programlisting">
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<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
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<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
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</pre>
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<p>
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Now, let's write a function object that prints XML of the form <type>data</type>
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for each member in the tuple.
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</p>
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<pre class="programlisting">
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<span class="keyword">struct</span> <span class="identifier">print_xml</span>
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<span class="special">{</span>
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<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">></span>
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<span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">T</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">x</span><span class="special">)</span> <span class="keyword">const</span>
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<span class="special">{</span>
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<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span>
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<span class="special"><<</span> <span class="char">'<'</span> <span class="special"><<</span> <span class="keyword">typeid</span><span class="special">(</span><span class="identifier">x</span><span class="special">).</span><span class="identifier">name</span><span class="special">()</span> <span class="special"><<</span> <span class="char">'>'</span>
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<span class="special"><<</span> <span class="identifier">x</span>
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<span class="special"><<</span> <span class="string">"</"</span> <span class="special"><<</span> <span class="keyword">typeid</span><span class="special">(</span><span class="identifier">x</span><span class="special">).</span><span class="identifier">name</span><span class="special">()</span> <span class="special"><<</span> <span class="char">'>'</span>
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<span class="special">;</span>
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<span class="special">}</span>
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<span class="special">};</span>
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</pre>
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<p>
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Now, finally:
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</p>
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<pre class="programlisting">
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<a href="algorithm/iteration/functions/for_each.html" title="for_each"><tt class="computeroutput"><span class="identifier">for_each</span></tt></a><span class="special">(</span><span class="identifier">stuff</span><span class="special">,</span> <span class="identifier">print_xml</span><span class="special">());</span>
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</pre>
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<p>
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That's it! <tt class="computeroutput"><a href="algorithm/iteration/functions/for_each.html" title="for_each"><tt class="computeroutput"><span class="identifier">for_each</span></tt></a></tt> is a fusion algorithm.
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It is a generic algorithm similar to <a href="http://en.wikipedia.org/wiki/Standard_Template_Library" target="_top">STL</a>'s.
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It iterates over the sequence and calls a user supplied function. In our case,
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it calls <tt class="computeroutput"><span class="identifier">print_xml</span></tt>'s <tt class="computeroutput"><span class="keyword">operator</span><span class="special">()</span></tt> for
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each element in <tt class="computeroutput"><span class="identifier">stuff</span></tt>.
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</p>
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<div class="caution"><table border="0" summary="Caution">
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<tr>
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<td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../../../../../doc/html/images/caution.png"></td>
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<th align="left">Caution</th>
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</tr>
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<tr><td colspan="2" align="left" valign="top"><p>
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The result of <tt class="computeroutput"><span class="keyword">typeid</span><span class="special">(</span><span class="identifier">x</span><span class="special">).</span><span class="identifier">name</span><span class="special">()</span></tt> is platform specific. The code here is
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just for exposition. Of course you already know that :-)
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</p></td></tr>
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</table></div>
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<p>
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<tt class="computeroutput"><a href="algorithm/iteration/functions/for_each.html" title="for_each"><tt class="computeroutput"><span class="identifier">for_each</span></tt></a></tt> is generic. With
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<tt class="computeroutput"><span class="identifier">print_xml</span></tt>, you can use it to
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print just about any Fusion <a href="sequence.html" title="Sequence">Sequence</a>.
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</p>
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<a name="fusion.quick_start.print_only_pointers"></a><h3>
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<a name="id457553"></a>
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<a href="quick_start.html#fusion.quick_start.print_only_pointers">Print only pointers</a>
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</h3>
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<p>
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Let's get a little cleverer. Say we wish to write a <span class="emphasis"><em>generic</em></span>
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function that takes in an arbitrary sequence and XML prints only those elements
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which are pointers. Ah, easy. First, let's include the <tt class="computeroutput"><span class="identifier">is_pointer</span></tt>
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boost type trait:
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</p>
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<pre class="programlisting">
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<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">/</span><span class="identifier">is_pointer</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
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</pre>
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<p>
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Then, simply:
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</p>
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<pre class="programlisting">
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<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Sequence</span><span class="special">></span>
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<span class="keyword">void</span> <span class="identifier">xml_print_pointers</span><span class="special">(</span><span class="identifier">Sequence</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">seq</span><span class="special">)</span>
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<span class="special">{</span>
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<a href="algorithm/iteration/functions/for_each.html" title="for_each"><tt class="computeroutput"><span class="identifier">for_each</span></tt></a><span class="special">(</span><a href="algorithm/transformation/functions/filter_if.html" title="filter_if"><tt class="computeroutput"><span class="identifier">filter_if</span></tt></a><span class="special"><</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">is_pointer</span><span class="special"><</span><span class="identifier">_</span><span class="special">></span> <span class="special">>(</span><span class="identifier">seq</span><span class="special">),</span> <span class="identifier">print_xml</span><span class="special">());</span>
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<span class="special">}</span>
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</pre>
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<p>
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<tt class="computeroutput"><a href="algorithm/transformation/functions/filter_if.html" title="filter_if"><tt class="computeroutput"><span class="identifier">filter_if</span></tt></a></tt> is another Fusion
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algorithm. It returns a <a href="view/filter_view.html" title="filter_view"><tt class="computeroutput"><span class="identifier">filter_view</span></tt></a>, a conforming Fusion sequence.
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This view reflects only those elements that pass the given predicate. In this
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case, the predicate is <tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">is_pointer</span><span class="special"><</span><span class="identifier">_</span><span class="special">></span></tt>.
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This "filtered view" is then passed to the <a href="algorithm/iteration/functions/for_each.html" title="for_each"><tt class="computeroutput"><span class="identifier">for_each</span></tt></a> algorithm, which then prints
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the "filtered view" as XML.
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</p>
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<p>
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Easy, right?
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</p>
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<a name="fusion.quick_start.associative_tuples"></a><h3>
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<a name="id457964"></a>
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<a href="quick_start.html#fusion.quick_start.associative_tuples">Associative tuples</a>
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</h3>
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<p>
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Ok, moving on...
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</p>
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<p>
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Apart from <tt class="computeroutput"><a href="container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a></tt>,
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fusion has a couple of other sequence types to choose from. Each sequence has
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its own characteristics. We have <tt class="computeroutput"><a href="container/list.html" title="list"><tt class="computeroutput"><span class="identifier">list</span></tt></a></tt>, <tt class="computeroutput"><a href="container/set.html" title="set"><tt class="computeroutput"><span class="identifier">set</span></tt></a></tt>, <tt class="computeroutput"><a href="container/map.html" title="map"><tt class="computeroutput"><span class="identifier">map</span></tt></a></tt>, plus a multitude of <tt class="computeroutput"><span class="identifier">views</span></tt> that provide various ways to present
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the sequences.
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</p>
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<p>
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Fusion's <tt class="computeroutput"><a href="container/map.html" title="map"><tt class="computeroutput"><span class="identifier">map</span></tt></a></tt>
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associate types with elements. It can be used as a cleverer replacement of
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the <tt class="computeroutput"><span class="keyword">struct</span></tt>. Example:
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</p>
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<pre class="programlisting">
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<span class="keyword">namespace</span> <span class="identifier">fields</span>
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<span class="special">{</span>
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<span class="keyword">struct</span> <span class="identifier">name</span><span class="special">;</span>
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<span class="keyword">struct</span> <span class="identifier">age</span><span class="special">;</span>
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<span class="special">}</span>
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<span class="keyword">typedef</span> <a href="container/map.html" title="map"><tt class="computeroutput"><span class="identifier">map</span></tt></a><span class="special"><</span>
|
||
<a href="support/pair.html" title="pair"><tt class="computeroutput"><span class="identifier">fusion</span><span class="special">::</span><span class="identifier">pair</span></tt></a><span class="special"><</span><span class="identifier">fields</span><span class="special">::</span><span class="identifier">name</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> <a href="support/pair.html" title="pair"><tt class="computeroutput"><span class="identifier">fusion</span><span class="special">::</span><span class="identifier">pair</span></tt></a><span class="special"><</span><span class="identifier">fields</span><span class="special">::</span><span class="identifier">age</span><span class="special">,</span> <span class="keyword">int</span><span class="special">></span> <span class="special">></span>
|
||
<span class="identifier">person</span><span class="special">;</span>
|
||
</pre>
|
||
<p>
|
||
<tt class="computeroutput"><a href="container/map.html" title="map"><tt class="computeroutput"><span class="identifier">map</span></tt></a></tt>
|
||
is an associative sequence. Its elements are Fusion pairs which differ somewhat
|
||
from <tt class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></tt>. Fusion pairs only contain one member,
|
||
with the type of their second template parameter. The first type parameter
|
||
of the pair is used as an index to the associated element in the sequence.
|
||
For example, given a <tt class="computeroutput"><span class="identifier">a_person</span></tt>
|
||
of type, <tt class="computeroutput"><span class="identifier">person</span></tt>, you can do:
|
||
</p>
|
||
<pre class="programlisting">
|
||
<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">fields</span><span class="special">;</span>
|
||
<span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">person_name</span> <span class="special">=</span> <a href="sequence/intrinsic/functions/at_key.html" title="at_key"><tt class="computeroutput"><span class="identifier">at_key</span></tt></a><span class="special"><</span><span class="identifier">name</span><span class="special">>(</span><span class="identifier">a_person</span><span class="special">);</span>
|
||
<span class="keyword">int</span> <span class="identifier">person_age</span> <span class="special">=</span> <a href="sequence/intrinsic/functions/at_key.html" title="at_key"><tt class="computeroutput"><span class="identifier">at_key</span></tt></a><span class="special"><</span><span class="identifier">age</span><span class="special">>(</span><span class="identifier">a_person</span><span class="special">);</span>
|
||
</pre>
|
||
<p>
|
||
Why go through all this trouble, you say? Well, for one, unlike the <tt class="computeroutput"><span class="keyword">struct</span></tt>, we are dealing with a generic data structure.
|
||
There are a multitude of facilities available at your disposal provided out
|
||
of the box with fusion or written by others. With these facilities, introspection
|
||
comes for free, for example. We can write one serialization function (well,
|
||
two, if you consider loading and saving) that will work for all your fusion
|
||
<tt class="computeroutput"><a href="container/map.html" title="map"><tt class="computeroutput"><span class="identifier">map</span></tt></a></tt>s.
|
||
Example:
|
||
</p>
|
||
<pre class="programlisting">
|
||
<span class="keyword">struct</span> <span class="identifier">saver</span>
|
||
<span class="special">{</span>
|
||
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Pair</span><span class="special">></span>
|
||
<span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">Pair</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">data</span><span class="special">)</span> <span class="keyword">const</span>
|
||
<span class="special">{</span>
|
||
<span class="identifier">some_archive</span> <span class="special"><<</span> <span class="identifier">data</span><span class="special">.</span><span class="identifier">second</span><span class="special">;</span>
|
||
<span class="special">}</span>
|
||
<span class="special">};</span>
|
||
|
||
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Stuff</span><span class="special">></span>
|
||
<span class="keyword">void</span> <span class="identifier">save</span><span class="special">(</span><span class="identifier">Stuff</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">stuff</span><span class="special">)</span>
|
||
<span class="special">{</span>
|
||
<a href="algorithm/iteration/functions/for_each.html" title="for_each"><tt class="computeroutput"><span class="identifier">for_each</span></tt></a><span class="special">(</span><span class="identifier">stuff</span><span class="special">,</span> <span class="identifier">saver</span><span class="special">());</span>
|
||
<span class="special">}</span>
|
||
</pre>
|
||
<p>
|
||
The <tt class="computeroutput"><span class="identifier">save</span></tt> function is generic
|
||
and will work for all types of <tt class="computeroutput"><span class="identifier">stuff</span></tt>
|
||
regardless if it is a <tt class="computeroutput"><span class="identifier">person</span></tt>,
|
||
a <tt class="computeroutput"><span class="identifier">dog</span></tt> or a whole <tt class="computeroutput"><span class="identifier">alternate_universe</span></tt>.
|
||
</p>
|
||
<a name="fusion.quick_start.tip_of_the_iceberg"></a><h3>
|
||
<a name="id459006"></a>
|
||
<a href="quick_start.html#fusion.quick_start.tip_of_the_iceberg">Tip of the Iceberg</a>
|
||
</h3>
|
||
<p>
|
||
And... we've barely scratched the surface! You can compose and expand the data
|
||
structures, remove elements from the structures, find specific data types,
|
||
query the elements, filter out types for inspection, transform data structures,
|
||
etc. What you've seen is just the tip of the iceberg.
|
||
</p>
|
||
<div class="footnotes">
|
||
<br><hr width="100" align="left">
|
||
<div class="footnote"><p><sup>[<a name="ftn.id456266" href="#id456266">1</a>] </sup>
|
||
There are finer grained header files available if you wish to have more
|
||
control over which components to include (see section <a href="organization.html" title="Organization">Orgainization</a>
|
||
for details).
|
||
</p></div>
|
||
<div class="footnote"><p><sup>[<a name="ftn.id456433" href="#id456433">2</a>] </sup>
|
||
Unless otherwise noted, components are in namespace <tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">fusion</span></tt>.
|
||
For the sake of simplicity, code in this quick start implies <tt class="computeroutput"><span class="keyword">using</span></tt> directives for the fusion components
|
||
we will be using.
|
||
</p></div>
|
||
</div>
|
||
</div>
|
||
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
|
||
<td align="left"></td>
|
||
<td align="right"><div class="copyright-footer">Copyright © 2001-2007 Joel de Guzman, Dan Marsden, Tobias
|
||
Schwinger<p>
|
||
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
||
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
|
||
</p>
|
||
</div></td>
|
||
</tr></table>
|
||
<hr>
|
||
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