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* omitted test_mpl_ops for now * made IndexSpecifierList a Mp11 sequence * made nested *_type_list's and tag Mp11 sequences * leftover MPL->Mp11 change * removed Clang 5.0 -std=c++1z as not supported by Mp11 * replaced boost::mpl::na with void as default index specifier arg * removed Clang 5.0 -std=c++1z as not supported by Mp11 (Drone) * replaced elementary MPL TMP with Mp11/std * replaced elementary MPL TMP with Mp11/std (tests) * leftover MPL #include * suppressed potential narrowing conversion warnings * enabled macro to support old interface, plus restored and augmented test_mpl_ops * removed secondary dependency to MPL thru Iterator * optimized Jamfile.v2 * added conditional support for old definition of tag * updated MPL support macro in tests * updated docs * stylistic * updated "cxxstd" in libraries.json * disabled test_serialization for Clang 3.5-3.6 due to lack of support from Boost.SmartPtr * fixed previous * removed no longer necessary workaround * removed redundant dependencies * updated test description
410 lines
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410 lines
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0.1 Transitional//EN">
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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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<title>Boost.MultiIndex Documentation - Tutorial - Techniques</title>
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<link rel="stylesheet" href="../style.css" type="text/css">
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<link rel="start" href="../index.html">
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<link rel="up" href="index.html">
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<link rel="next" href="../reference/index.html">
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</head>
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<body>
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<h1><img src="../../../../boost.png" alt="boost.png (6897 bytes)" align=
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"middle" width="277" height="86">Boost.MultiIndex Tutorial: Techniques</h1>
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<div class="prev_link"><a href="debug.html"><img src="../prev.gif" alt="debugging support" border="0"><br>
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Debugging support
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</a></div>
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<div class="up_link"><a href="index.html"><img src="../up.gif" alt="Boost.MultiIndex tutorial" border="0"><br>
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Boost.MultiIndex tutorial
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</a></div>
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<div class="next_link"><a href="../reference/index.html"><img src="../next.gif" alt="Boost.MultiIndex reference" border="0"><br>
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Boost.MultiIndex reference
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</a></div><br clear="all" style="clear: all;">
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<hr>
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<h2>Contents</h2>
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<ul>
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<li><a href="#emulate_std_containers">Emulating standard containers with
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<code>multi_index_container</code></a>
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<ul>
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<li><a href="#emulate_assoc_containers">Emulation of associative
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containers</a></li>
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<li><a href="#emulate_std_list">Emulation of <code>std::list</code></a></li>
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</ul>
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</li>
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<li><a href="#metaprogrammming">Metaprogramming and <code>multi_index_container</code></a>
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<ul>
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<li><a href="#analysis">Analysis</a></li>
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<li><a href="#synthesis">Synthesis</a></li>
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</ul>
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</li>
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</ul>
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<h2><a name="emulate_std_containers">Emulating standard containers with
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<code>multi_index_container</code></a></h2>
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<h3><a name="emulate_assoc_containers">Emulation of associative
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containers</a></h3>
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<p>
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Academic motivations aside, there is a practical interest in emulating standard
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associative containers by means of <code>multi_index_container</code>, namely to take
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advantage of extended functionalities provided by <code>multi_index_container</code> for
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lookup, range querying and updating.
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</p>
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<p>
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In order to emulate a <code>std::set</code> one can follow the substitution
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rule:
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>set</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>Compare</span><span class=special>,</span><span class=identifier>Allocator</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Key</span><span class=special>,</span>
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<span class=identifier>indexed_by</span><span class=special><</span><span class=identifier>ordered_unique</span><span class=special><</span><span class=identifier>identity</span><span class=special><</span><span class=identifier>Key</span><span class=special>>,</span><span class=identifier>Compare</span><span class=special>></span> <span class=special>>,</span>
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<span class=identifier>Allocator</span>
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<span class=special>></span>
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</pre></blockquote>
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<p>
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In the default case where <code>Compare=std::less<Key></code> and
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<code>Allocator=std::allocator<Key></code>, the substitution rule is
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simplified as
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>set</span><span class=special><</span><span class=identifier>Key</span><span class=special>></span> <span class=special>-></span> <span class=identifier>multi_index_container</span><span class=special><</span><span class=identifier>Key</span><span class=special>></span>
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</pre></blockquote>
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<p>
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The substitution of <code>multi_index_container</code> for <code>std::set</code> keeps
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the whole set of functionality provided by <code>std::set</code>, so in
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principle it is a drop-in replacement needing no further adjustments.
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</p>
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<p>
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<code>std::multiset</code> can be emulated in a similar manner, according to the
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following rule:
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>multiset</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>Compare</span><span class=special>,</span><span class=identifier>Allocator</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Key</span><span class=special>,</span>
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<span class=identifier>indexed_by</span><span class=special><</span><span class=identifier>ordered_non_unique</span><span class=special><</span><span class=identifier>identity</span><span class=special><</span><span class=identifier>Key</span><span class=special>>,</span><span class=identifier>Compare</span><span class=special>></span> <span class=special>>,</span>
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<span class=identifier>Allocator</span>
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<span class=special>></span>
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</pre></blockquote>
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<p>
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When default values are taken into consideration, the rule takes the form
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>multiset</span><span class=special><</span><span class=identifier>Key</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Key</span><span class=special>,</span>
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<span class=identifier>indexed_by</span><span class=special><</span><span class=identifier>ordered_non_unique</span><span class=special><</span><span class=identifier>identity</span><span class=special><</span><span class=identifier>Key</span><span class=special>></span> <span class=special>></span> <span class=special>></span>
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<span class=special>></span>
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</pre></blockquote>
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<p>
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The emulation of <code>std::multiset</code>s with <code>multi_index_container</code>
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results in a slight difference with respect to the interface offered: the member
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function <code>insert(const value_type&)</code> does not return an
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<code>iterator</code> as in <code>std::multiset</code>s, but rather a
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<code>std::pair<iterator,bool></code> in the spirit of <code>std::set</code>s.
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In this particular case, however, the <code>bool</code> member of the returned
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pair is always <code>true</code>.
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</p>
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<p>
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The case of <code>std::map</code>s and <code>std::multimap</code>s does not lend
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itself to such a direct emulation by means of <code>multi_index_container</code>. The main
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problem lies in the fact that elements of a <code>multi_index_container</code> are treated
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as constant, while the <code>std::map</code> and <code>std::multimap</code> handle
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objects of type <code>std::pair<const Key,T></code>, thus allowing for free
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modification of the value part. To overcome this difficulty we need to create an ad
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hoc pair class:
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</p>
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<blockquote><pre>
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<span class=keyword>template</span> <span class=special><</span><span class=keyword>typename</span> <span class=identifier>T1</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>T2</span><span class=special>></span>
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<span class=keyword>struct</span> <span class=identifier>mutable_pair</span>
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<span class=special>{</span>
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<span class=keyword>typedef</span> <span class=identifier>T1</span> <span class=identifier>first_type</span><span class=special>;</span>
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<span class=keyword>typedef</span> <span class=identifier>T2</span> <span class=identifier>second_type</span><span class=special>;</span>
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<span class=identifier>mutable_pair</span><span class=special>():</span><span class=identifier>first</span><span class=special>(</span><span class=identifier>T1</span><span class=special>()),</span><span class=identifier>second</span><span class=special>(</span><span class=identifier>T2</span><span class=special>()){}</span>
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<span class=identifier>mutable_pair</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>T1</span><span class=special>&</span> <span class=identifier>f</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>T2</span><span class=special>&</span> <span class=identifier>s</span><span class=special>):</span><span class=identifier>first</span><span class=special>(</span><span class=identifier>f</span><span class=special>),</span><span class=identifier>second</span><span class=special>(</span><span class=identifier>s</span><span class=special>){}</span>
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<span class=identifier>mutable_pair</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>pair</span><span class=special><</span><span class=identifier>T1</span><span class=special>,</span><span class=identifier>T2</span><span class=special>>&</span> <span class=identifier>p</span><span class=special>):</span><span class=identifier>first</span><span class=special>(</span><span class=identifier>p</span><span class=special>.</span><span class=identifier>first</span><span class=special>),</span><span class=identifier>second</span><span class=special>(</span><span class=identifier>p</span><span class=special>.</span><span class=identifier>second</span><span class=special>){}</span>
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<span class=identifier>T1</span> <span class=identifier>first</span><span class=special>;</span>
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<span class=keyword>mutable</span> <span class=identifier>T2</span> <span class=identifier>second</span><span class=special>;</span>
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<span class=special>};</span>
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</pre></blockquote>
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<p>
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and so the substitution rules are:
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>map</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>T</span><span class=special>,</span><span class=identifier>Compare</span><span class=special>,</span><span class=identifier>Allocator</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Element</span><span class=special>,</span>
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<span class=identifier>indexed_by</span><span class=special><</span>
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<span class=identifier>ordered_unique</span><span class=special><</span><span class=identifier>member</span><span class=special><</span><span class=identifier>Element</span><span class=special>,</span><span class=identifier>Key</span><span class=special>,&</span><span class=identifier>Element</span><span class=special>::</span><span class=identifier>first</span><span class=special>>,</span><span class=identifier>Compare</span><span class=special>></span>
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<span class=special>>,</span>
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<span class=keyword>typename</span> <span class=identifier>Allocator</span><span class=special>::</span><span class=keyword>template</span> <span class=identifier>rebind</span><span class=special><</span><span class=identifier>Element</span><span class=special>>::</span><span class=identifier>other</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>multimap</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>T</span><span class=special>,</span><span class=identifier>Compare</span><span class=special>,</span><span class=identifier>Allocator</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Element</span><span class=special>,</span>
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<span class=identifier>indexed_by</span><span class=special><</span>
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<span class=identifier>ordered_non_unique</span><span class=special><</span><span class=identifier>member</span><span class=special><</span><span class=identifier>Element</span><span class=special>,</span><span class=identifier>Key</span><span class=special>,&</span><span class=identifier>Element</span><span class=special>::</span><span class=identifier>first</span><span class=special>>,</span><span class=identifier>Compare</span><span class=special>></span>
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<span class=special>>,</span>
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<span class=keyword>typename</span> <span class=identifier>Allocator</span><span class=special>::</span><span class=keyword>template</span> <span class=identifier>rebind</span><span class=special><</span><span class=identifier>Element</span><span class=special>>::</span><span class=identifier>other</span>
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<span class=special>></span>
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(<span class=identifier>with</span> <span class=identifier>Element</span><span class=special>=</span><span class=identifier>mutable_pair</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>T</span><span class=special>></span>)
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</pre></blockquote>
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<p>
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If default values are considered, the rules take the form:
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>map</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>T</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Element</span><span class=special>,
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</span><span class=identifier>indexed_by</span><span class=special><</span><span class=identifier>ordered_unique</span><span class=special><</span><span class=identifier>member</span><span class=special><</span><span class=identifier>Element</span><span class=special>,</span><span class=identifier>Key</span><span class=special>,&</span><span class=identifier>Element</span><span class=special>::</span><span class=identifier>first</span><span class=special>></span> <span class=special>></span> <span class=special>></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>multimap</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>T</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Element</span><span class=special>,
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</span><span class=identifier>indexed_by</span><span class=special><</span><span class=identifier>ordered_non_unique</span><span class=special><</span><span class=identifier>member</span><span class=special><</span><span class=identifier>Element</span><span class=special>,</span><span class=identifier>Key</span><span class=special>,&</span><span class=identifier>Element</span><span class=special>::</span><span class=identifier>first</span><span class=special>></span> <span class=special>></span> <span class=special>></span>
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<span class=special>></span>
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(<span class=identifier>with</span> <span class=identifier>Element</span><span class=special>=</span><span class=identifier>mutable_pair</span><span class=special><</span><span class=identifier>Key</span><span class=special>,</span><span class=identifier>T</span><span class=special>></span>)
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</pre></blockquote>
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<p>
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Unlike as with standard sets, the interface of these <code>multi_index_container</code>-emulated
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maps does not exactly conform to that of <code>std::map</code>s and
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<code>std::multimap</code>s. The most obvious difference is the lack of
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<code>operator []</code>, either in read or write mode; this, however, can be
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emulated with appropriate use of <code>find</code> and <code>insert</code>.
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</p>
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<p>
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These emulations of standard associative containers with <code>multi_index_container</code>
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are comparable to the original constructs in terms of space and time efficiency.
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See the <a href="../performance.html">performance section</a> for further details.
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</p>
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<h3><a name="emulate_std_list">Emulation of <code>std::list</code></a></h3>
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<p>
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Unlike the case of associative containers, emulating <code>std::list</code>
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in Boost.MultiIndex does not add any significant functionality, so the following
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is presented merely for completeness sake.
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</p>
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<p>
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Much as with standard maps, the main difficulty to overcome when emulating
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<code>std::list</code> derives from the constant nature of elements of a
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<code>multi_index_container</code>. Again, some sort of adaption class is needed, like
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for instance the following:
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</p>
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<blockquote><pre>
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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>struct</span> <span class=identifier>mutable_value</span>
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<span class=special>{</span>
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<span class=identifier>mutable_value</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>T</span><span class=special>&</span> <span class=identifier>t</span><span class=special>):</span><span class=identifier>t</span><span class=special>(</span><span class=identifier>t</span><span class=special>){}</span>
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<span class=keyword>operator</span> <span class=identifier>T</span><span class=special>&()</span><span class=keyword>const</span><span class=special>{</span><span class=keyword>return</span> <span class=identifier>t</span><span class=special>;}</span>
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<span class=keyword>private</span><span class=special>:</span>
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<span class=keyword>mutable</span> <span class=identifier>T</span> <span class=identifier>t</span><span class=special>;</span>
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<span class=special>};</span>
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</pre></blockquote>
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<p>
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which allows us to use the substitution rule:
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>list</span><span class=special><</span><span class=identifier>T</span><span class=special>,</span><span class=identifier>Allocator</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span>
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<span class=identifier>Element</span><span class=special>,</span>
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<span class=identifier>indexed_by</span><span class=special><</span><span class=identifier>sequenced</span><span class=special><></span> <span class=special>>,</span>
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<span class=keyword>typename</span> <span class=identifier>Allocator</span><span class=special>::</span><span class=keyword>template</span> <span class=identifier>rebind</span><span class=special><</span><span class=identifier>Element</span><span class=special>>::</span><span class=identifier>other</span>
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<span class=special>></span>
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(<span class=identifier>with</span> <span class=identifier>Element</span><span class=special>=</span><span class=identifier>mutable_value</span><span class=special><</span><span class=identifier>T</span><span class=special>></span>)
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</pre></blockquote>
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<p>
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or, if the default value <code>Allocator=std::allocator<T></code> is used:
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</p>
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<blockquote><pre>
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<span class=identifier>std</span><span class=special>::</span><span class=identifier>list</span><span class=special><</span><span class=identifier>T</span><span class=special>></span> <span class=special>-></span>
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<span class=identifier>multi_index_container</span><span class=special><</span><span class=identifier>mutable_value</span><span class=special><</span><span class=identifier>T</span><span class=special>>,</span><span class=identifier>indexed_by</span><span class=special><</span><span class=identifier>sequenced</span><span class=special><></span> <span class=special>></span> <span class=special>></span>
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</pre></blockquote>
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<h2><a name="metaprogrammming">Metaprogramming and <code>multi_index_container</code></a></h2>
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<p>
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Boost.MultiIndex provides a number of facilities intended to allow the analysis and
|
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synthesis of <code>multi_index_container</code> instantiations with metaprogramming.
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</p>
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<h3><a name="analysis">Analysis</a></h3>
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<p>
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Given a <code>multi_index_container</code> instantiation, the following nested types are
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provided for compile-time inspection of the various types occurring in the
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definition of the <code>multi_index_container</code>:
|
|
<ul>
|
|
<li><code>index_specifier_type_list</code>,</li>
|
|
<li><code>index_type_list</code>,</li>
|
|
<li><code>iterator_type_list</code>,</li>
|
|
<li><code>const_iterator_type_list</code>.</li>
|
|
</ul>
|
|
Each of these types is an
|
|
<a href="../../../../libs/mp11/doc/html/mp11.html#definitions">Mp11 list</a>
|
|
with as many elements as indices
|
|
comprise the <code>multi_index_container</code>: for instance, the <code>n</code>-th
|
|
element of <code>iterator_type_list</code> is the same as
|
|
<code>nth_index<n>::type::iterator</code>. Boost.Mp11 makes it very easy
|
|
to inspect and manipulate these lists:
|
|
</p>
|
|
|
|
<blockquote><pre>
|
|
<span class=keyword>using</span> <span class=identifier>indexed_t</span><span class=special>=</span><span class=identifier>multi_index_container</span><span class=special><</span>
|
|
<span class=keyword>int</span><span class=special>,</span>
|
|
<span class=identifier>indexed_by</span><span class=special><</span>
|
|
<span class=identifier>ordered_unique</span><span class=special><</span><span class=identifier>identity</span><span class=special><</span><span class=keyword>int</span><span class=special>></span> <span class=special>>,</span>
|
|
<span class=identifier>sequenced</span><span class=special><></span>
|
|
<span class=special>></span>
|
|
<span class=special>>;</span>
|
|
|
|
<span class=identifier>boost</span><span class=special>::</span><span class=identifier>mp11</span><span class=special>::</span><span class=identifier>mp_for_each</span><span class=special><</span><span class=identifier>indexed_t</span><span class=special>::</span><span class=identifier>index_specifier_type_list</span><span class=special>>([](</span><span class=keyword>auto</span> <span class=identifier>I</span><span class=special>){</span>
|
|
<span class=identifier>std</span><span class=special>::</span><span class=identifier>cout</span> <span class=special><<</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>typeindex</span><span class=special>::</span><span class=identifier>type_id</span><span class=special><</span><span class=identifier>decltype</span><span class=special>(</span><span class=identifier>I</span><span class=special>)>().</span><span class=identifier>pretty_name</span><span class=special>()</span> <span class=special><<</span> <span class=string>"\n"</span><span class=special>;</span>
|
|
<span class=special>});</span>
|
|
|
|
<span class=comment>// Output:
|
|
//
|
|
// struct boost::multi_index::ordered_unique<struct boost::multi_index::identity<int>,void,void>
|
|
// struct boost::multi_index::sequenced<struct boost::multi_index::tag<> ></span>
|
|
</pre></blockquote>
|
|
|
|
<p>
|
|
A subtle but important distinction exists between
|
|
<code>index_specifier_type_list</code> and <code>index_type_list</code>:
|
|
the former list holds the index <i>specifiers</i>
|
|
with which the <code>multi_index_container</code> instantiation was defined,
|
|
while the latter gives access to the actual implementation classes
|
|
corresponding to each specifier. In the example above,
|
|
<code>indexed_t::index_specifier_type_list</code> is a type list with
|
|
elements
|
|
</p>
|
|
|
|
<blockquote><pre>
|
|
<span class=identifier>ordered_unique</span><span class=special><</span><span class=identifier>identity</span><span class=special><</span><span class=keyword>int</span><span class=special>></span><span class=special>></span>
|
|
<span class=identifier>sequenced</span><span class=special><></span>
|
|
</pre></blockquote>
|
|
|
|
<p>
|
|
while <code>indexed_t::index_type_list</code> holds the types
|
|
</p>
|
|
|
|
<blockquote><pre>
|
|
<span class=identifier>multi_index_container</span><span class=special>::</span><span class=identifier>nth_type</span><span class=special><</span><span class=number>0</span><span class=special>>::</span><span class=identifier>type</span>
|
|
<span class=identifier>multi_index_container</span><span class=special>::</span><span class=identifier>nth_type</span><span class=special><</span><span class=number>1</span><span class=special>>::</span><span class=identifier>type</span>
|
|
</pre></blockquote>
|
|
|
|
<p>
|
|
so the lists are radically different.
|
|
</p>
|
|
|
|
<h3><a name="synthesis">Synthesis</a></h3>
|
|
|
|
<p>
|
|
Although typically indices are specified by means of the
|
|
<code>indexed_by</code> construct, actually any Mp11 list can be provided instead:
|
|
</p>
|
|
|
|
<blockquote><pre>
|
|
<span class=keyword>using</span> <span class=identifier>index_list_t</span><span class=special>=</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>tuple</span><span class=special><</span><span class=identifier>ordered_unique</span><span class=special><</span><span class=identifier>identity</span><span class=special><</span><span class=keyword>int</span><span class=special>></span> <span class=special>>,</span><span class=identifier>sequenced</span><span class=special><>></span> <span class=special>;</span>
|
|
|
|
<span class=keyword>typedef</span> <span class=identifier>multi_index_container</span><span class=special><</span>
|
|
<span class=keyword>int</span><span class=special>,</span>
|
|
<span class=identifier>index_list_t</span>
|
|
<span class=special>></span> <span class=identifier>indexed_t</span><span class=special>;</span>
|
|
</pre></blockquote>
|
|
|
|
<p>
|
|
This possibility enables the synthesis of instantiations of
|
|
<code>multi_index_container</code> through metaprogramming, as the following
|
|
example shows:
|
|
</p>
|
|
|
|
<blockquote><pre>
|
|
<span class=comment>// original multi_index_container instantiation</span>
|
|
<span class=keyword>using</span> <span class=identifier>indexed_t1</span><span class=special>=</span><span class=identifier>multi_index_container</span><span class=special><</span>
|
|
<span class=keyword>int</span><span class=special>,</span>
|
|
<span class=identifier>indexed_by</span><span class=special><</span>
|
|
<span class=identifier>ordered_unique</span><span class=special><</span><span class=identifier>identity</span><span class=special><</span><span class=keyword>int</span><span class=special>></span> <span class=special>></span>
|
|
<span class=special>></span>
|
|
<span class=special>>;</span>
|
|
|
|
<span class=comment>// we take its index list and add an index</span>
|
|
<span class=keyword>using</span> <span class=identifier>index_list_t2</span><span class=special>=</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>mp11</span><span class=special>::</span><span class=identifier>mp_push_front</span><span class=special><</span>
|
|
<span class=identifier>indexed_t1</span><span class=special>::</span><span class=identifier>index_specifier_type_list</span><span class=special>,</span>
|
|
<span class=identifier>sequenced</span><span class=special><></span>
|
|
<span class=special>>;</span>
|
|
|
|
<span class=comment>// augmented multi_index_container</span>
|
|
<span class=keyword>using</span> <span class=identifier>indexed_t2</span><span class=special>=</span><span class=identifier>multi_index_container</span><span class=special><</span>
|
|
<span class=keyword>int</span><span class=special>,</span>
|
|
<span class=identifier>index_list_t2</span>
|
|
<span class=special>>;</span>
|
|
</pre></blockquote>
|
|
|
|
<hr>
|
|
|
|
<div class="prev_link"><a href="debug.html"><img src="../prev.gif" alt="debugging support" border="0"><br>
|
|
Debugging support
|
|
</a></div>
|
|
<div class="up_link"><a href="index.html"><img src="../up.gif" alt="Boost.MultiIndex tutorial" border="0"><br>
|
|
Boost.MultiIndex tutorial
|
|
</a></div>
|
|
<div class="next_link"><a href="../reference/index.html"><img src="../next.gif" alt="Boost.MultiIndex reference" border="0"><br>
|
|
Boost.MultiIndex reference
|
|
</a></div><br clear="all" style="clear: all;">
|
|
|
|
<br>
|
|
|
|
<p>Revised October 25th 2025</p>
|
|
|
|
<p>© Copyright 2003-2025 Joaquín M López Muñoz.
|
|
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">
|
|
http://www.boost.org/LICENSE_1_0.txt</a>)
|
|
</p>
|
|
|
|
</body>
|
|
</html>
|