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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0.1 Transitional//EN">
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<title>Boost.MultiIndex Documentation - Hashed indices reference</title>
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<h1><img src="../../../../boost.png" alt="boost.png (6897 bytes)" align=
"middle" width="277" height="86">Boost.MultiIndex Hashed indices reference</h1>
<div class="prev_link"><a href="ord_indices.html"><img src="../prev.gif" alt="ordered indices" border="0"><br>
Ordered indices
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Boost.MultiIndex reference
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Sequenced indices
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<hr>
<h2>Contents</h2>
<ul>
<li><a href="#hash_index_fwd_synopsis">Header
<code>"boost/multi_index/hashed_index_fwd.hpp"</code> synopsis</a></li>
<li><a href="#synopsis">Header
<code>"boost/multi_index/hashed_index.hpp"</code> synopsis</a>
<ul>
<li><a href="#unique_non_unique">
Index specifiers <code>hashed_unique</code> and <code>hashed_non_unique</code>
</a></li>
<li><a href="#hash_indices">Hashed indices</a>
<ul>
<li><a href="#complexity_signature">Complexity signature</a></li>
<li><a href="#instantiation_types">Instantiation types</a></li>
<li><a href="#types">Nested types</a></li>
<li><a href="#constructors">Constructors, copy and assignment</a></li>
<li><a href="#modifiers">Modifiers</a></li>
<li><a href="#observers">Observers</a></li>
<li><a href="#lookup">Lookup</a></li>
<li><a href="#hash_policy">Hash policy</a></li>
<li><a href="#serialization">Serialization</a></li>
</ul>
</li>
</ul>
</li>
</ul>
<h2>
<a name="hash_index_fwd_synopsis">Header
<a href="../../../../boost/multi_index/hashed_index_fwd.hpp">
<code>"boost/multi_index/hashed_index_fwd.hpp"</code></a> synopsis</a></h2>
<blockquote><pre>
<span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span>
<span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span>
<span class=comment>// index specifiers hashed_unique and hashed_non_unique</span>
<span class=keyword>template</span><span class=special><</span><b>consult hashed_unique reference for arguments</b><span class=special>></span>
<span class=keyword>struct</span> <span class=identifier>hashed_unique</span><span class=special>;</span>
<span class=keyword>template</span><span class=special><</span><b>consult hashed_non_unique reference for arguments</b><span class=special>></span>
<span class=keyword>struct</span> <span class=identifier>hashed_non_unique</span><span class=special>;</span>
<span class=comment>// indices</span>
<span class=keyword>namespace</span> <span class=identifier>detail</span><span class=special>{</span>
<span class=keyword>template</span><span class=special><</span><b>implementation defined</b><span class=special>></span> <span class=keyword>class</span> <b>index name is implementation defined</b><span class=special>;</span>
<span class=special>}</span> <span class=comment>// namespace boost::multi_index::detail</span>
<span class=special>}</span> <span class=comment>// namespace boost::multi_index</span>
<span class=special>}</span> <span class=comment>// namespace boost</span>
</pre></blockquote>
<p>
<code>hashed_index_fwd.hpp</code> provides forward declarations for index specifiers
<a href="#unique_non_unique"><code>hashed_unique</code> and <code>hashed_non_unique</code></a> and
their associated <a href="#hash_indices">hashed index</a> classes.
</p>
<h2>
<a name="synopsis">Header
<a href="../../../../boost/multi_index/hashed_index.hpp">
<code>"boost/multi_index/hashed_index.hpp"</code></a> synopsis</a></h2>
<blockquote><pre>
<span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span>
<span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span>
<span class=comment>// index specifiers hashed_unique and hashed_non_unique</span>
<span class=keyword>template</span><span class=special><</span><b>consult hashed_unique reference for arguments</b><span class=special>></span>
<span class=keyword>struct</span> <span class=identifier>hashed_unique</span><span class=special>;</span>
<span class=keyword>template</span><span class=special><</span><b>consult hashed_non_unique reference for arguments</b><span class=special>></span>
<span class=keyword>struct</span> <span class=identifier>hashed_non_unique</span><span class=special>;</span>
<span class=comment>// indices</span>
<span class=keyword>namespace</span> <span class=identifier>detail</span><span class=special>{</span>
<span class=keyword>template</span><span class=special><</span><b>implementation defined</b><span class=special>></span> <span class=keyword>class</span> <b>index class name implementation defined</b><span class=special>;</span>
<span class=comment>// index specialized algorithms:</span>
<span class=keyword>template</span><span class=special><</span><b>implementation defined</b><span class=special>></span>
<span class=keyword>void</span> <span class=identifier>swap</span><span class=special>(</span><b>index class name</b><span class=special>&</span> <span class=identifier>x</span><span class=special>,</span><b>index class name</b><span class=special>&</span> <span class=identifier>y</span><span class=special>);</span>
<span class=special>}</span> <span class=comment>// namespace boost::multi_index::detail</span>
<span class=special>}</span> <span class=comment>// namespace boost::multi_index</span>
<span class=special>}</span> <span class=comment>// namespace boost</span>
</pre></blockquote>
<h3><a name="unique_non_unique">
Index specifiers <code>hashed_unique</code> and <code>hashed_non_unique</code>
</a></h3>
<p>
These <a href="indices.html#index_specification">index specifiers</a> allow
for insertion of <a href="#hash_indices">hashed indices</a> without and with
allowance of duplicate elements, respectively. The syntax of <code>hashed_unique</code>
and <code>hashed_non_unique</code> coincide, thus we describe them in a grouped manner.
<code>hashed_unique</code> and <code>hashed_non_unique</code> can be instantiated in
two different forms, according to whether a tag list for the index is provided or not:
</p>
<blockquote><pre>
<span class=keyword>template</span><span class=special><</span>
<span class=keyword>typename</span> <span class=identifier>KeyFromValue</span><span class=special>,</span>
<span class=keyword>typename</span> <span class=identifier>Hash</span><span class=special>=</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>hash</span><span class=special><</span><span class=identifier>KeyFromValue</span><span class=special>::</span><span class=identifier>result_type</span><span class=special>>,</span>
<span class=keyword>typename</span> <span class=identifier>Pred</span><span class=special>=</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>equal_to</span><span class=special><</span><span class=identifier>KeyFromValue</span><span class=special>::</span><span class=identifier>result_type</span><span class=special>></span>
<span class=special>></span>
<span class=keyword>struct</span> <span class=special>(</span><span class=identifier>hashed_unique</span> <span class=special>|</span> <span class=identifier>hashed_non_unique</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>TagList</span><span class=special>,</span>
<span class=keyword>typename</span> <span class=identifier>KeyFromValue</span><span class=special>,</span>
<span class=keyword>typename</span> <span class=identifier>Hash</span><span class=special>=</span><span class=identifier>boost</span><span class=special>::</span><span class=identifier>hash</span><span class=special><</span><span class=identifier>KeyFromValue</span><span class=special>::</span><span class=identifier>result_type</span><span class=special>>,</span>
<span class=keyword>typename</span> <span class=identifier>Pred</span><span class=special>=</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>equal_to</span><span class=special><</span><span class=identifier>KeyFromValue</span><span class=special>::</span><span class=identifier>result_type</span><span class=special>></span>
<span class=special>></span>
<span class=keyword>struct</span> <span class=special>(</span><span class=identifier>hashed_unique</span> <span class=special>|</span> <span class=identifier>hashed_non_unique</span><span class=special>)</span><span class=special>;</span>
</pre></blockquote>
<p>
If provided, <code>TagList</code> must be an instantiation of the class template
<a href="indices.html#tag"><code>tag</code></a>.
The template arguments are used by the corresponding index implementation,
refer to the <a href="#hash_indices">hashed indices</a> reference section for further
explanations on their acceptable type values.
</p>
<h3><a name="hash_indices">Hashed indices</a></h3>
<p>
A hashed index provides fast retrieval of elements of a <code>multi_index_container</code>
through hashing tecnhiques. The interface and semantics of hashed indices are modeled according
to the proposal for unordered associative containers given in the C++
<a href="http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1836.pdf">Proposed
Draft Tecnhical Report on Standard Library Extensions</a>, also known as TR1. A hashed
index is particularized according to a given
<a href="key_extraction.html#key_extractors"><code>Key Extractor</code></a>
that retrieves keys from elements of <code>multi_index_container</code>, a <code>Hash</code>
function object which returns hash values for the keys and a binary predicate <code>Pred</code>
acting as an equivalence relation on values of <code>Key</code>.
</p>
<p>
There are two variants of hashed indices: <i>unique</i>, which do
not allow duplicate elements (with respect to its associated equality
predicate) and <i>non-unique</i>, which accept those duplicates.
The interface of these two variants is the same, so they are documented
together, with minor differences explicitly stated when they exist.
</p>
<p>
Except where noted, hashed indices (both unique and non-unique) are models of
<code>Unordered Associative Container</code>, in the spirit of
<code>std::tr1::unordered_set</code>s. Validity of iterators and references to
elements is preserved in all cases. Occasionally, the exception safety guarantees provided
are actually stronger than required by the extension draft. We only provide descriptions
of those types and operations that are either not present in the concepts modeled or
do not exactly conform to the requirements for unordered associative containers.
</p>
<blockquote><pre>
<span class=keyword>namespace</span> <span class=identifier>boost</span><span class=special>{</span>
<span class=keyword>namespace</span> <span class=identifier>multi_index</span><span class=special>{</span>
<span class=keyword>namespace</span> <span class=identifier>detail</span><span class=special>{</span>
<span class=keyword>template</span><span class=special><</span><b>implementation defined: dependent on types Value, Allocator,
TagList, KeyFromValue, Hash, Pred</b><span class=special>></span>
<span class=keyword>class</span> <b>name is implementation defined</b>
<span class=special>{</span>
<span class=keyword>public</span><span class=special>:</span>
<span class=comment>// types:</span>
<span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>KeyFromValue</span><span class=special>::</span><span class=identifier>result_type</span> <span class=identifier>key_type</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=identifier>Value</span> <span class=identifier>value_type</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=identifier>KeyFromValue</span> <span class=identifier>key_from_value</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=identifier>Hash</span> <span class=identifier>hasher</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=identifier>Pred</span> <span class=identifier>key_equal</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=identifier>tuple</span><span class=special><</span>
<span class=identifier>size_type</span><span class=special>,</span><span class=identifier>key_from_value</span><span class=special>,</span><span class=identifier>hasher</span><span class=special>,</span><span class=identifier>key_equal</span><span class=special>></span> <span class=identifier>ctor_args</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=identifier>Allocator</span> <span class=identifier>allocator_type</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>Allocator</span><span class=special>::</span><span class=identifier>pointer</span> <span class=identifier>pointer</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>Allocator</span><span class=special>::</span><span class=identifier>const_pointer</span> <span class=identifier>const_pointer</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>Allocator</span><span class=special>::</span><span class=identifier>reference</span> <span class=identifier>reference</span><span class=special>;</span>
<span class=keyword>typedef</span> <span class=keyword>typename</span> <span class=identifier>Allocator</span><span class=special>::</span><span class=identifier>const_reference</span> <span class=identifier>const_reference</span><span class=special>;</span>
<span class=keyword>typedef</span> <b>implementation defined </b><span class=identifier>size_type</span><span class=special>;</span>
<span class=keyword>typedef</span> <b>implementation defined </b><span class=identifier>difference_type</span><span class=special>;</span>
<span class=keyword>typedef</span> <b>implementation defined </b><span class=identifier>iterator</span><span class=special>;</span>
<span class=keyword>typedef</span> <b>implementation defined </b><span class=identifier>const_iterator</span><span class=special>;</span>
<span class=keyword>typedef</span> <b>implementation defined </b><span class=identifier>local_iterator</span><span class=special>;</span>
<span class=keyword>typedef</span> <b>implementation defined </b><span class=identifier>const_local_iterator</span><span class=special>;</span>
<span class=comment>// construct/destroy/copy:</span>
<b>index class name</b><span class=special>&</span> <span class=keyword>operator</span><span class=special>=(</span><span class=keyword>const</span> <b>index class name</b><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span>
<span class=identifier>allocator_type</span> <span class=identifier>get_allocator</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=comment>// size and capacity:</span>
<span class=keyword>bool</span> <span class=identifier>empty</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>size_type</span> <span class=identifier>size</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>size_type</span> <span class=identifier>max_size</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=comment>// iterators:</span>
<span class=identifier>iterator</span> <span class=identifier>begin</span><span class=special>();</span>
<span class=identifier>const_iterator</span> <span class=identifier>begin</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>iterator</span> <span class=identifier>end</span><span class=special>();</span>
<span class=identifier>const_iterator</span> <span class=identifier>end</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=comment>// modifiers:</span>
<span class=identifier>std</span><span class=special>::</span><span class=identifier>pair</span><span class=special><</span><span class=identifier>iterator</span><span class=special>,</span><span class=keyword>bool</span><span class=special>></span> <span class=identifier>insert</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>value_type</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span>
<span class=identifier>iterator</span> <span class=identifier>insert</span><span class=special>(</span><span class=identifier>iterator</span> <span class=identifier>position</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>value_type</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span>
<span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>InputIterator</span><span class=special>></span>
<span class=keyword>void</span> <span class=identifier>insert</span><span class=special>(</span><span class=identifier>InputIterator</span> <span class=identifier>first</span><span class=special>,</span><span class=identifier>InputIterator</span> <span class=identifier>last</span><span class=special>);</span>
<span class=identifier>iterator</span> <span class=identifier>erase</span><span class=special>(</span><span class=identifier>iterator</span> <span class=identifier>position</span><span class=special>);</span>
<span class=identifier>size_type</span> <span class=identifier>erase</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>key_type</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span>
<span class=identifier>iterator</span> <span class=identifier>erase</span><span class=special>(</span><span class=identifier>iterator</span> <span class=identifier>first</span><span class=special>,</span><span class=identifier>iterator</span> <span class=identifier>last</span><span class=special>);</span>
<span class=keyword>bool</span> <span class=identifier>replace</span><span class=special>(</span><span class=identifier>iterator</span> <span class=identifier>position</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>value_type</span><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span>
<span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Modifier</span><span class=special>></span> <span class=keyword>bool</span> <span class=identifier>modify</span><span class=special>(</span><span class=identifier>iterator</span> <span class=identifier>position</span><span class=special>,</span><span class=identifier>Modifier</span> <span class=identifier>mod</span><span class=special>);</span>
<span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>Modifier</span><span class=special>></span> <span class=keyword>bool</span> <span class=identifier>modify_key</span><span class=special>(</span><span class=identifier>iterator</span> <span class=identifier>position</span><span class=special>,</span><span class=identifier>Modifier</span> <span class=identifier>mod</span><span class=special>);</span>
<span class=keyword>void</span> <span class=identifier>clear</span><span class=special>();</span>
<span class=keyword>void</span> <span class=identifier>swap</span><span class=special>(</span><b>index class name</b><span class=special>&</span> <span class=identifier>x</span><span class=special>);</span>
<span class=comment>// observers:</span>
<span class=identifier>key_from_value</span> <span class=identifier>key_extractor</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>hasher</span> <span class=identifier>hash_function</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>key_equal</span> <span class=identifier>key_eq</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=comment>// lookup:</span>
<span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompatibleKey</span><span class=special>></span>
<span class=identifier>iterator</span> <span class=identifier>find</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>CompatibleKey</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>template</span><span class=special><</span>
<span class=keyword>typename</span> <span class=identifier>CompatibleKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompatibleHash</span><span class=special>,</span> <span class=keyword>typename</span> <span class=identifier>CompatiblePred</span>
<span class=special>></span>
<span class=identifier>iterator</span> <span class=identifier>find</span><span class=special>(</span>
<span class=keyword>const</span> <span class=identifier>CompatibleKey</span><span class=special>&</span> <span class=identifier>x</span><span class=special>,</span>
<span class=keyword>const</span> <span class=identifier>CompatibleHash</span><span class=special>&</span> <span class=identifier>hash</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>CompatiblePred</span><span class=special>&</span> <span class=identifier>eq</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompatibleKey</span><span class=special>></span>
<span class=identifier>size_type</span> <span class=identifier>count</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>CompatibleKey</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>template</span><span class=special><</span>
<span class=keyword>typename</span> <span class=identifier>CompatibleKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompatibleHash</span><span class=special>,</span> <span class=keyword>typename</span> <span class=identifier>CompatiblePred</span>
<span class=special>></span>
<span class=identifier>size_type</span> <span class=identifier>count</span><span class=special>(</span>
<span class=keyword>const</span> <span class=identifier>CompatibleKey</span><span class=special>&</span> <span class=identifier>x</span><span class=special>,</span>
<span class=keyword>const</span> <span class=identifier>CompatibleHash</span><span class=special>&</span> <span class=identifier>hash</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>CompatiblePred</span><span class=special>&</span> <span class=identifier>eq</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>template</span><span class=special><</span><span class=keyword>typename</span> <span class=identifier>CompatibleKey</span><span class=special>></span>
<span class=identifier>std</span><span class=special>::</span><span class=identifier>pair</span><span class=special><</span><span class=identifier>iterator</span><span class=special>,</span><span class=identifier>iterator</span><span class=special>></span> <span class=identifier>equal_range</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>CompatibleKey</span><span class=special>&</span> <span class=identifier>x</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>template</span><span class=special><</span>
<span class=keyword>typename</span> <span class=identifier>CompatibleKey</span><span class=special>,</span><span class=keyword>typename</span> <span class=identifier>CompatibleHash</span><span class=special>,</span> <span class=keyword>typename</span> <span class=identifier>CompatiblePred</span>
<span class=special>></span>
<span class=identifier>std</span><span class=special>::</span><span class=identifier>pair</span><span class=special><</span><span class=identifier>iterator</span><span class=special>,</span><span class=identifier>iterator</span><span class=special>></span> <span class=identifier>equal_range</span><span class=special>(</span>
<span class=keyword>const</span> <span class=identifier>CompatibleKey</span><span class=special>&</span> <span class=identifier>x</span><span class=special>,
</span><span class=keyword>const</span> <span class=identifier>CompatibleHash</span><span class=special>&</span> <span class=identifier>hash</span><span class=special>,</span><span class=keyword>const</span> <span class=identifier>CompatiblePred</span><span class=special>&</span> <span class=identifier>eq</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=comment>// bucket interface:</span>
<span class=identifier>size_type</span> <span class=identifier>bucket_count</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>size_type</span> <span class=identifier>max_bucket_count</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>size_type</span> <span class=identifier>bucket_size</span><span class=special>(</span><span class=identifier>size_type</span> <span class=identifier>n</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>size_type</span> <span class=identifier>bucket</span><span class=special>(</span><span class=keyword>const</span> <span class=identifier>key_type</span><span class=special>&</span> <span class=identifier>k</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>local_iterator</span> <span class=identifier>begin</span><span class=special>(</span><span class=identifier>size_type</span> <span class=identifier>n</span><span class=special>);</span>
<span class=identifier>const_local_iterator</span> <span class=identifier>begin</span><span class=special>(</span><span class=identifier>size_type</span> <span class=identifier>n</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=identifier>local_iterator</span> <span class=identifier>end</span><span class=special>(</span><span class=identifier>size_type</span> <span class=identifier>n</span><span class=special>);</span>
<span class=identifier>const_local_iterator</span> <span class=identifier>end</span><span class=special>(</span><span class=identifier>size_type</span> <span class=identifier>n</span><span class=special>)</span><span class=keyword>const</span><span class=special>;</span>
<span class=comment>// hash policy:</span>
<span class=keyword>float</span> <span class=identifier>load_factor</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>float</span> <span class=identifier>max_load_factor</span><span class=special>()</span><span class=keyword>const</span><span class=special>;</span>
<span class=keyword>void</span> <span class=identifier>max_load_factor</span><span class=special>(</span><span class=keyword>float</span> <span class=identifier>z</span><span class=special>);</span>
<span class=keyword>void</span> <span class=identifier>rehash</span><span class=special>(</span><span class=identifier>size_type</span> <span class=identifier>n</span><span class=special>);</span>
<span class=special>};</span>
<span class=comment>// index specialized algorithms:</span>
<span class=keyword>template</span><span class=special><</span><b>implementation defined</b><span class=special>></span>
<span class=keyword>void</span> <span class=identifier>swap</span><span class=special>(</span><b>index class name</b><span class=special>&</span> <span class=identifier>x</span><span class=special>,</span><b>index class name</b><span class=special>&</span> <span class=identifier>y</span><span class=special>);</span>
<span class=special>}</span> <span class=comment>// namespace boost::multi_index::detail</span>
<span class=special>}</span> <span class=comment>// namespace boost::multi_index</span>
<span class=special>}</span> <span class=comment>// namespace boost</span>
</pre></blockquote>
<h4><a name="complexity_signature">Complexity signature</a></h4>
<p>
Here and in the descriptions of operations of hashed indices, we adopt the
scheme outlined in the
<a href="indices.html#complexity_signature">complexity signature
section</a>. The complexity signature of hashed indices is:
<ul>
<li>copying: <code>c(n)=n*log(n)</code>,</li>
<li>insertion: average case <code>i(n)=1</code> (constant),
worst case <code>i(n)=n</code>,</li>
<li>hinted insertion: average case <code>h(n)=1</code> (constant),
worst case <code>h(n)=n</code>,</li>
<li>deletion: average case <code>d(n)=1</code> (constant),
worst case <code>d(n)=n</code>,</li>
<li>replacement:
<ul>
<li>if the new element key is equivalent to the original, <code>r(n)=1</code> (constant),</li>
<li>otherwise, average case <code>r(n)=1</code> (constant),
worst case <code>r(n)=n</code>,</li>
</ul></li>
<li>modifying: average case <code>m(n)=1</code> (constant),
worst case <code>m(n)=n</code>.</li>
</ul>
</p>
<h4><a name="instantiation_types">Instantiation types</a></h4>
<p>Hashed indices are instantiated internally to <code>multi_index_container</code> and
specified by means of <a href="indices.html#indexed_by"><code>indexed_by</code></a>
with <a href="#unique_non_unique"> index specifiers <code>hashed_unique</code>
and <code>hashed_non_unique</code></a>. Instantiations are dependent on the
following types:
<ul>
<li><code>Value</code> from <code>multi_index_container</code>,</li>
<li><code>Allocator</code> from <code>multi_index_container</code>,</li>
<li><code>TagList</code> from the index specifier (if provided),</li>
<li><code>KeyFromValue</code> from the index specifier,</li>
<li><code>Hash</code> from the index specifier,</li>
<li><code>Pred</code> from the index specifier.</li>
</ul>
<code>TagList</code> must be an instantiation of
<a href="indices.html#tag"><code>tag</code></a>. The type <code>KeyFromValue</code>,
which determines the mechanism for extracting a key from <code>Value</code>,
must be a model of <a href="key_extraction.html#key_extractors">
<code>Key Extractor</code></a> from <code>Value</code>. <code>Hash</code> is a
<a href="http://www.sgi.com/tech/stl/UnaryFunction.html"><code>Unary Function</code></a>
taking a single argument of type <code>KeyFromValue::result_type</code> and returning a
value of type <code>std::size_t</code> in the range
<code>[0, std::numeric_limits<std::size_t>::max())</code>.
<code>Pred</code> is a
<a href="http://www.sgi.com/tech/stl/BinaryPredicate.html">
<code>Binary Predicate</code></a> inducing an equivalence relation
on elements of <code>KeyFromValue::result_type</code>. It is required that
the <code>Hash</code> object return the same value for keys
equivalent under <code>Pred</code>.
</p>
<h4><a name="types">Nested types</a></h4>
<code>ctor_args</code>
<blockquote>
The first element of this tuple indicates the minimum number of buckets
set up by the index on construction time. If the default value 0 is used,
an implementation defined number is used instead.
</blockquote>
<code>iterator<br>
const_iterator<br>
local_iterator<br>
const_local_iterator</code>
<blockquote>
These types are models of
<a href="http://www.sgi.com/tech/stl/ForwardIterator.html"><code>Forward
Iterator</code></a>.
</blockquote>
<h4><a name="constructors">Constructors, copy and assignment</a></h4>
<p>
As explained in the <a href="indices.html#index_concepts">index
concepts section</a>, indices do not have public constructors or destructors.
Assignment, on the other hand, is provided. Upon construction,
<code>max_load_factor()</code> is 1.0.
</p>
<code><b>index class name</b>& operator=(const <b>index class name</b>& x);</code>
<blockquote>
<b>Effects:</b>
<blockquote><pre>
<span class=identifier>a</span><span class=special>=</span><span class=identifier>b</span><span class=special>;</span>
</pre></blockquote>
where <code>a</code> and <code>b</code> are the <code>multi_index_container</code>
objects to which <code>*this</code> and <code>x</code> belong, respectively.<br>
<b>Returns:</b> <code>*this</code>.<br>
</blockquote>
<h4><a name="modifiers">Modifiers</a></h4>
<code>std::pair<iterator,bool> insert(const value_type& x);</code>
<blockquote>
<b>Effects:</b> Inserts <code>x</code> into the <code>multi_index_container</code> to which
the index belongs if
<ul>
<li>the index is non-unique OR no other element exists with
equivalent key,</li>
<li>AND insertion is allowed by all other indices of the
<code>multi_index_container</code>.</li>
</ul>
<b>Returns:</b> The return value is a pair <code>p</code>. <code>p.second</code>
is <code>true</code> if and only if insertion took place. On successful insertion,
<code>p.first</code> points to the element inserted; otherwise, <code>p.first</code>
points to an element that caused the insertion to be banned. Note that more than
one element can be causing insertion not to be allowed.<br>
<b>Complexity:</b> <code>O(I(n))</code>.<br>
<b>Exception safety:</b> Strong.<br>
</blockquote>
<code>iterator insert(iterator position,const value_type& x);</code>
<blockquote>
<b>Requires:</b> <code>position</code> is a valid iterator of the index.</br>
<b>Effects:</b> Inserts <code>x</code> into the <code>multi_index_container</code> to which
the index belongs if
<ul>
<li>the index is non-unique OR no other element exists with
equivalent key,</li>
<li>AND insertion is allowed by all other indices of the
<code>multi_index_container</code>.</li>
</ul>
<code>position</code> is used as a hint to improve the efficiency of the
operation.<br>
<b>Returns:</b> On successful insertion, an iterator to the newly inserted
element. Otherwise, an iterator to an element that caused the insertion to be
banned. Note that more than one element can be causing insertion not to be
allowed.<br>
<b>Complexity:</b> <code>O(H(n))</code>.<br>
<b>Exception safety:</b> Strong.<br>
</blockquote>
<code>template<typename InputIterator><br>
void insert(InputIterator first,InputIterator last);</code>
<blockquote>
<b>Requires:</b> <code>InputIterator</code> is a model of
<a href="http://www.sgi.com/tech/stl/InputIterator.html">
<code>Input Iterator</code></a> over elements of type
<code>value_type</code> or a type convertible to <code>value_type</code>.
<code>first</code> and <code>last</code> are not iterators into any
index of the <code>multi_index_container</code> to which this index belongs.
<code>last</code> is reachable from <code>first</code>.</br>
<b>Effects:</b>
<blockquote><pre>
<span class=identifier>iterator</span> <span class=identifier>hint</span><span class=special>=</span><span class=identifier>end</span><span class=special>();</span>
<span class=keyword>while</span><span class=special>(</span><span class=identifier>first</span><span class=special>!=</span><span class=identifier>last</span><span class=special>)</span><span class=identifier>hint</span><span class=special>=</span><span class=identifier>insert</span><span class=special>(</span><span class=identifier>hint</span><span class=special>,*</span><span class=identifier>first</span><span class=special>++);</span>
</pre></blockquote>
<b>Complexity:</b> <code>O(m*H(n+m))</code>, where
<code>m</code> is the number of elements in [<code>first</code>,
<code>last</code>).<br>
<b>Exception safety:</b> Basic.<br>
</blockquote>
<code>iterator erase(iterator position);</code>
<blockquote>
<b>Requires:</b> <code>position</code> is a valid dereferenceable iterator
of the index.</br>
<b>Effects:</b> Deletes the element pointed to by <code>position</code>.<br>
<b>Returns:</b> An iterator pointing to the element immediately following
the one that was deleted, or <code>end()</code>
if no such element exists.<br>
<b>Complexity:</b> <code>O(D(n))</code>.<br>
<b>Exception safety:</b> <code>nothrow</code>.<br>
</blockquote>
<code>size_type erase(const key_type& x);</code>
<blockquote>
<b>Effects:</b> Deletes the elements with key equivalent to <code>x</code>.<br>
<b>Returns:</b> Number of elements deleted.<br>
<b>Complexity:</b> Average case, <code>O(1 + m*D(n))</code>, worst case
<code>O(n + m*D(n))</code>, where <code>m</code> is
the number of elements deleted.<br>
<b>Exception safety:</b> Basic.<br>
</blockquote>
<code>iterator erase(iterator first,iterator last);</code>
<blockquote>
<b>Requires:</b> [<code>first</code>,<code>last</code>) is a valid
range of the index.<br>
<b>Effects:</b> Deletes the elements in [<code>first</code>,<code>last</code>).<br>
<b>Returns:</b> <code>last</code>.<br>
<b>Complexity:</b> <code>O(m*D(n))</code>, where <code>m</code> is
the number of elements in [<code>first</code>,<code>last</code>).<br>
<b>Exception safety:</b> <code>nothrow</code>.<br>
</blockquote>
<a name="replace"><code>bool replace(iterator position,const value_type& x);</code></a>
<blockquote>
<b>Requires:</b> <code>position</code> is a valid dereferenceable iterator
of the index.</br>
<b>Effects:</b> Assigns the value <code>x</code> to the element pointed
to by <code>position</code> into the <code>multi_index_container</code> to which
the index belongs if, for the value <code>x</code>
<ul>
<li>the index is non-unique OR no other element exists
(except possibly <code>*position</code>) with equivalent key,</li>
<li>AND replacing is allowed by all other indices of the
<code>multi_index_container</code>.</li>
</ul>
<b>Postconditions:</b> Validity of <code>position</code> is preserved
in all cases.<br>
<b>Returns:</b> <code>true</code> if the replacement took place,
<code>false</code> otherwise.<br>
<b>Complexity:</b> <code>O(R(n))</code>.<br>
<b>Exception safety:</b> Strong. If an exception is thrown by some
user-provided operation the <code>multi_index_container</code> to which the index
belongs remains in its original state.
</blockquote>
<a name="modify">
<code>template<typename Modifier> bool modify(iterator position,Modifier mod);</code></a>
<blockquote>
<b>Requires:</b> <code>Modifier</code> is a model of
<a href="http://www.sgi.com/tech/stl/UnaryFunction.html">
<code>Unary Function</code></a> accepting arguments of type
<code>value_type&</code>. <code>position</code> is a valid dereferenceable
iterator of the index.</br>
<b>Effects:</b> Calls <code>mod(e)</code> where <code>e</code> is the element
pointed to by <code>position</code> and rearranges <code>*position</code> into
all the indices of the <code>multi_index_container</code>. Rearrangement is successful if
<ul>
<li>the index is non-unique OR no other element exists
with equivalent key,</li>
<li>AND rearrangement is allowed by all other indices of the
<code>multi_index_container</code>.</li>
</ul>
If the rearrangement fails, the element is erased.<br>
<b>Postconditions:</b> Validity of <code>position</code> is preserved if the
operation succeeds.<br>
<b>Returns:</b> <code>true</code> if the operation succeeded, <code>false</code>
otherwise.<br>
<b>Complexity:</b> <code>O(M(n))</code>.<br>
<b>Exception safety:</b> Basic. If an exception is thrown by some
user-provided operation (except possibly <code>mod</code>), then
the element pointed to by <code>position</code> is erased.
</blockquote>
<a name="modify_key">
<code>template<typename Modifier> bool modify_key(iterator position,Modifier mod);</code></a>
<blockquote>
<b>Requires:</b> <code>key_from_value</code> is a read/write
<a href="key_extraction.html#key_extractors"><code>Key Extractor</code></a>
from <code>value_type</code>. <code>Modifier</code> is a model of
<a href="http://www.sgi.com/tech/stl/UnaryFunction.html">
<code>Unary Function</code></a> accepting arguments of type
<code>key_type&</code>. <code>position</code> is a valid dereferenceable
iterator of the index.</br>
<b>Effects:</b> Calls <code>mod(k)</code> where <code>k</code> is the key
obtained by the internal <code>KeyFromValue</code> object of the index from
the element pointed to by <code>position</code>, and rearranges
<code>*position</code> into all the indices of the <code>multi_index_container</code>.
Rearrangement is successful if
<ul>
<li>the index is non-unique OR no other element exists
with equivalent key,</li>
<li>AND rearrangement is allowed by all other indices of the
<code>multi_index_container</code>.</li>
</ul>
If the rearrangement fails, the element is erased.<br>
<b>Postconditions:</b>Validity of <code>position</code> is preserved if
the operation succeeds.<br>
<b>Returns:</b> <code>true</code> if the operation succeeded, <code>false</code>
otherwise.<br>
<b>Complexity:</b> <code>O(M(n))</code>.<br>
<b>Exception safety:</b> Basic. If an exception is thrown by some
user-provided operation (except possibly <code>mod</code>), then
the element pointed to by <code>position</code> is erased.
</blockquote>
<h4><a name="observers">Observers</a></h4>
<p>Apart from standard <code>hash_function</code> and <code>key_eq</code>,
hashed indices have a member function for retrieving the internal key extractor
used.
</p>
<code>key_from_value key_extractor()const;</code>
<blockquote>
Returns a copy of the <code>key_from_value</code> object used to construct
the index.<br>
<b>Complexity:</b> Constant.
</blockquote>
<h4><a name="lookup">Lookup</a></h4>
<p>
Hashed indices provide the full lookup functionality required by
unordered associative containers, namely <code>find</code>,
<code>count</code>, and <code>equal_range</code>. Additionally,
these member functions are templatized to allow for non-standard
arguments, so extending the types of search operations allowed.
The kind of arguments permissible when invoking the lookup member
functions is defined by the following concept.
</p>
<p>
Consider a pair (<code>Hash</code>, <code>Pred</code>) where
<code>Hash</code> is a hash functor over values of type <code>Key</code>
and <code>Pred</code> is a
<a href="http://www.sgi.com/tech/stl/BinaryPredicate.html">
<code>Binary Predicate</code></a> inducing an equivalence relation
on <code>Key</code>, with the additional constraint that equivalent
keys have the same hash value.
A triplet of types (<code>CompatibleKey</code>, <code>CompatibleHash</code>,
<code>CompatiblePred</code>) is said to be a <i>compatible extension</i>
of (<code>Hash</code>, <code>Pred</code>) if
<ol>
<li><code>CompatibleHash</code> is a hash functor on values of
type <code>CompatibleKey</code>,</li>
<li><code>CompatiblePred</code> is a
<a href="http://www.sgi.com/tech/stl/BinaryPredicate.html">
<code>Binary Predicate</code></a> over (<code>Key</code>,
<code>CompatibleKey</code>),</li>
<li><code>CompatiblePred</code> is a
<a href="http://www.sgi.com/tech/stl/BinaryPredicate.html">
<code>Binary Predicate</code></a> over (<code>CompatibleKey</code>,
<code>Key</code>),</li>
<li>if <code>c_eq(ck,k1)</code> then <code>c_eq(k1,ck)</code>,</li>
<li>if <code>c_eq(ck,k1)</code> and <code>eq(k1,k2)</code> then
<code>c_eq(ck,k2)</code>,</li>
<li>if <code>c_eq(ck,k1)</code> and <code>c_eq(ck,k2)</code> then
<code>eq(k1,k2)</code>,</li>
<li>if <code>c_eq(ck,k1)</code> then <code>c_hash(ck)==hash(k1)</code>,</li>
</ol>
for every <code>c_hash</code> of type <code>CompatibleHash</code>,
<code>c_eq</code> of type <code>CompatiblePred</code>,
<code>hash</code> of type <code>Hash</code>,
<code>eq</code> of type <code>Pred</code>, <code>ck</code> of type
<code>CompatibleKey</code> and <code>k1</code>, <code>k2</code> of type
<code>Key</code>.
</p>
<p>Additionally, a type <code>CompatibleKey</code> is said to be a
<i>compatible key</i> of (<code>Hash</code>, <code>Pred</code>) if
(<code>CompatibleKey</code>, <code>Hash</code>, <code>Pred</code>)
is a compatible extension of (<code>Hash</code>, <code>Pred</code>).
This implies that <code>Hash</code> and <code>Pred</code> accept arguments
of type <code>CompatibleKey</code>, which usually means they have
several overloads of therir corresponding <code>operator()</code>
member functions.
</p>
<p>
In the context of a compatible extension or a compatible key, the expression
"equivalent key" takes on its obvious interpretation.
</p>
<code>template<typename CompatibleKey> iterator find(const CompatibleKey& x)const;
</code>
<blockquote>
<b>Requires:</b> <code>CompatibleKey</code> is a compatible key of
(<code>hasher</code>, <code>key_equal</code>).</br>
<b>Effects:</b> Returns a pointer to an element whose key is equivalent to
<code>x</code>, or <code>end()</code> if such an element does not exist.<br>
<b>Complexity:</b> Average case <code>O(1)</code> (constant), worst case
<code>O(n)</code>.<br>
</blockquote>
<code>template<<br>
typename CompatibleKey,typename CompatibleHash, typename CompatiblePred<br>
><br>
iterator find(<br>
const CompatibleKey& x,<br>
const CompatibleHash& hash,const CompatiblePred& eq)const;
</code>
<blockquote>
<b>Requires:</b> (<code>CompatibleKey</code>, <code>CompatibleHash</code>,
<code>CompatiblePred</code>) is a compatible extension of
(<code>hasher</code>, <code>key_equal</code>).</br>
<b>Effects:</b> Returns a pointer to an element whose key is equivalent to
<code>x</code>, or <code>end()</code> if such an element does not exist.<br>
<b>Complexity:</b> Average case <code>O(1)</code> (constant), worst case
<code>O(n)</code>.<br>
</blockquote>
<code>template<typename CompatibleKey><br>
size_type count(const CompatibleKey& x)const;
</code>
<blockquote>
<b>Requires:</b> <code>CompatibleKey</code> is a compatible key of
(<code>hasher</code>, <code>key_equal</code>).</br>
<b>Effects:</b> Returns the number of elements with key equivalent to <code>x</code>.<br>
<b>Complexity:</b> Average case <code>O(count(x))</code>, worst case
<code>O(n)</code>.<br>
</blockquote>
<code>template<<br>
typename CompatibleKey,typename CompatibleHash, typename CompatiblePred<br>
><br>
size_type count(<br>
const CompatibleKey& x,<br>
const CompatibleHash& hash,const CompatiblePred& eq)const;
</code>
<blockquote>
<b>Requires:</b> (<code>CompatibleKey</code>, <code>CompatibleHash</code>,
<code>CompatiblePred</code>) is a compatible extension of
(<code>hasher</code>, <code>key_equal</code>).</br>
<b>Effects:</b> Returns the number of elements with key equivalent to <code>x</code>.<br>
<b>Complexity:</b> Average case <code>O(count(x,hash,eq))</code>, worst case
<code>O(n)</code>.<br>
</blockquote>
<code>template<typename CompatibleKey><br>
std::pair<iterator,iterator> equal_range(const CompatibleKey& x)const;
</code>
<blockquote>
<b>Requires:</b> <code>CompatibleKey</code> is a compatible key of
(<code>hasher</code>, <code>key_equal</code>).</br>
<b>Effects:</b> Returns a range containing all elements with keys equivalent
to <code>x</code> (and only those).<br>
<b>Complexity:</b> Average case <code>O(count(x))</code>, worst case
<code>O(n)</code>.<br>
</blockquote>
<code>template<<br>
typename CompatibleKey,typename CompatibleHash, typename CompatiblePred<br>
><br>
std::pair<iterator,iterator> equal_range(</br>
const CompatibleKey& x,<br>
const CompatibleHash& hash,const CompatiblePred& eq)const;
</code>
<blockquote>
<b>Requires:</b> (<code>CompatibleKey</code>, <code>CompatibleHash</code>,
<code>CompatiblePred</code>) is a compatible extension of
(<code>hasher</code>, <code>key_equal</code>).</br>
<b>Effects:</b> Returns a range containing all elements with keys equivalent
to <code>x</code> (and only those).<br>
<b>Complexity:</b> Average case <code>O(count(x,hash,eq))</code>, worst case
<code>O(n)</code>.<br>
</blockquote>
<h4><a name="hash_policy">Hash policy</a></h4>
<code>void rehash(size_type n);</code>
<blockquote>
<b>Effects:</b> Increases if necessary the number of internal buckets
so that <code>size()/bucket_count()</code> does not exceed the maximum
load factor, and <code>bucket_count()>=n</code>.<br>
<b>Postconditions:</b> Validity of iterators and references to the
elements contained is preserved.<br>
<b>Complexity:</b> Average case <code>O(size())</code>, worst case
<code>O(size(n)<sup>2</sup>)</code>.<br>
<b>Exception safety:</b> Strong.
</blockquote>
<h4><a name="serialization">Serialization</a></h4>
<p>
Indices cannot be serialized on their own, but only as part of the
<code>multi_index_container</code> into which they are embedded. In describing
the additional preconditions and guarantees associated to hashed indices
with respect to serialization of their embedding containers, we
use the concepts defined in the <code>multi_index_container</code>
<a href="multi_index_container.html#serialization">serialization section</a>.
</p>
Operation: saving of a <code>multi_index_container</code> <code>m</code> to an
output archive (XML archive) <code>ar</code>.
<blockquote>
<b>Requires:</b> No additional requirements to those imposed by the container.
</blockquote>
Operation: loading of a <code>multi_index_container</code> <code>m'</code> from an
input archive (XML archive) <code>ar</code>.
<blockquote>
<b>Requires:</b> Additionally to the general requirements, <code>key_eq()</code>
must be serialization-compatible with <code>m.get<i>().key_eq()</code>,
where <code>i</code> is the position of the hashed index in the container.<br>
<b>Postconditions:</b> On succesful loading, the range
[<code>begin()</code>, <code>end()</code>) contains restored copies of every
element in [<code>m.get<i>().begin()</code>, <code>m.get<i>().end()</code>),
though not necessarily in the same order.
</blockquote>
Operation: saving of an <code>iterator</code> or <code>const_iterator</code>
<code>it</code> to an output archive (XML archive) <code>ar</code>.
<blockquote>
<b>Requires:</b> <code>it</code> is a valid iterator of the index. The associated
<code>multi_index_container</code> has been previously saved.
</blockquote>
Operation: loading of an <code>iterator</code> or <code>const_iterator</code>
<code>it'</code> from an input archive (XML archive) <code>ar</code>.
<blockquote>
<b>Postconditions:</b> On succesful loading, if <code>it</code> was dereferenceable
then <code>*it'</code> is the restored copy of <code>*it</code>, otherwise
<code>it'==end()</code>.<br>
<b>Note:</b> It is allowed that <code>it</code> be a <code>const_iterator</code>
and the restored <code>it'</code> an <code>iterator</code>, or viceversa.
</blockquote>
Operation: saving of a <code>local_iterator</code> or
<code>const_local_iterator</code>
<code>it</code> to an output archive (XML archive) <code>ar</code>.
<blockquote>
<b>Requires:</b> <code>it</code> is a valid local iterator of the index. The
associated <code>multi_index_container</code> has been previously saved.
</blockquote>
Operation: loading of a <code>local_iterator</code> or
<code>const_local_iterator</code>
<code>it'</code> from an input archive (XML archive) <code>ar</code>.
<blockquote>
<b>Postconditions:</b> On succesful loading, if <code>it</code> was dereferenceable
then <code>*it'</code> is the restored copy of <code>*it</code>; if <code>it</code>
was <code>m.get<i>().end(n)</code> for some <code>n</code>, then
<code>it'==m'.get<i>().end(n)</code> (where <code>m</code> is the original
<code>multi_index_container</code>, <code>m'</code> its restored copy
and <code>i</code> is the ordinal of the index.)<br>
<b>Note:</b> It is allowed that <code>it</code> be a <code>const_local_iterator</code>
and the restored <code>it'</code> a <code>local_iterator</code>, or viceversa.
</blockquote>
<hr>
<div class="prev_link"><a href="ord_indices.html"><img src="../prev.gif" alt="ordered indices" border="0"><br>
Ordered indices
</a></div>
<div class="up_link"><a href="index.html"><img src="../up.gif" alt="Boost.MultiIndex reference" border="0"><br>
Boost.MultiIndex reference
</a></div>
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Sequenced indices
</a></div><br clear="all" style="clear: all;">
<br>
<p>Revised July 13th 2006</p>
<p>© Copyright 2003-2006 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>
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