1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>Class template unordered_map</title> 6<link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> 7<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 8<link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> 9<link rel="up" href="../unordered/reference.html#header.boost.unordered_map_hpp" title="Header <boost/unordered_map.hpp>"> 10<link rel="prev" href="unordered/node_handle_map.html" title="Class template node_handle_map"> 11<link rel="next" href="unordered_multimap.html" title="Class template unordered_multimap"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../boost.png"></td> 16<td align="center"><a href="../../../index.html">Home</a></td> 17<td align="center"><a href="../../../libs/libraries.htm">Libraries</a></td> 18<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 19<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 20<td align="center"><a href="../../../more/index.htm">More</a></td> 21</tr></table> 22<hr> 23<div class="spirit-nav"> 24<a accesskey="p" href="unordered/node_handle_map.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../unordered/reference.html#header.boost.unordered_map_hpp"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="unordered_multimap.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="refentry"> 27<a name="boost.unordered_map"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Class template unordered_map</span></h2> 30<p>boost::unordered_map — 31 An unordered associative container that associates unique keys with another value. 32 </p> 33</div> 34<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 35<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../unordered/reference.html#header.boost.unordered_map_hpp" title="Header <boost/unordered_map.hpp>">boost/unordered_map.hpp</a>> 36 37</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Mapped<span class="special">,</span> <span class="keyword">typename</span> Hash <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">Key</span><span class="special">></span><span class="special">,</span> 38 <span class="keyword">typename</span> Pred <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">Key</span><span class="special">></span><span class="special">,</span> 39 <span class="keyword">typename</span> Alloc <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">allocator</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">Key</span> <span class="keyword">const</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">>></span> <span class="special">></span> 40<span class="keyword">class</span> <a class="link" href="unordered_map.html" title="Class template unordered_map">unordered_map</a> <span class="special">{</span> 41<span class="keyword">public</span><span class="special">:</span> 42 <span class="comment">// <a class="link" href="unordered_map.html#boost.unordered_maptypes">types</a></span> 43 <span class="keyword">typedef</span> <span class="identifier">Key</span> <a name="boost.unordered_map.key_type"></a><span class="identifier">key_type</span><span class="special">;</span> 44 <span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">Key</span> <span class="keyword">const</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">></span> <a name="boost.unordered_map.value_type"></a><span class="identifier">value_type</span><span class="special">;</span> 45 <span class="keyword">typedef</span> <span class="identifier">Mapped</span> <a name="boost.unordered_map.mapped_type"></a><span class="identifier">mapped_type</span><span class="special">;</span> 46 <span class="keyword">typedef</span> <span class="identifier">Hash</span> <a name="boost.unordered_map.hasher"></a><span class="identifier">hasher</span><span class="special">;</span> 47 <span class="keyword">typedef</span> <span class="identifier">Pred</span> <a name="boost.unordered_map.key_equal"></a><span class="identifier">key_equal</span><span class="special">;</span> 48 <span class="keyword">typedef</span> <span class="identifier">Alloc</span> <a name="boost.unordered_map.allocator_type"></a><span class="identifier">allocator_type</span><span class="special">;</span> 49 <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">allocator_type</span><span class="special">::</span><span class="identifier">pointer</span> <a class="link" href="unordered_map.html#boost.unordered_map.pointer"><span class="identifier">pointer</span></a><span class="special">;</span> 50 <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">allocator_type</span><span class="special">::</span><span class="identifier">const_pointer</span> <a class="link" href="unordered_map.html#boost.unordered_map.const_pointer"><span class="identifier">const_pointer</span></a><span class="special">;</span> 51 <span class="keyword">typedef</span> <span class="identifier">value_type</span><span class="special">&</span> <a name="boost.unordered_map.reference"></a><span class="identifier">reference</span><span class="special">;</span> <span class="comment">// lvalue of value_type.</span> 52 <span class="keyword">typedef</span> <span class="identifier">value_type</span> <span class="keyword">const</span><span class="special">&</span> <a name="boost.unordered_map.const_reference"></a><span class="identifier">const_reference</span><span class="special">;</span> <span class="comment">// const lvalue of value_type.</span> 53 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.size_type"><span class="identifier">size_type</span></a><span class="special">;</span> 54 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.difference_type"><span class="identifier">difference_type</span></a><span class="special">;</span> 55 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.iterator"><span class="identifier">iterator</span></a><span class="special">;</span> 56 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.const_iterator"><span class="identifier">const_iterator</span></a><span class="special">;</span> 57 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.local_iterator"><span class="identifier">local_iterator</span></a><span class="special">;</span> 58 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.const_local_iterator"><span class="identifier">const_local_iterator</span></a><span class="special">;</span> 59 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.node_type"><span class="identifier">node_type</span></a><span class="special">;</span> 60 <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a class="link" href="unordered_map.html#boost.unordered_map.insert_return_type"><span class="identifier">insert_return_type</span></a><span class="special">;</span> 61 62 <span class="comment">// <a class="link" href="unordered_map.html#boost.unordered_mapconstruct-copy-destruct">construct/copy/destruct</a></span> 63 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_22-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 64 <span class="keyword">explicit</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_23-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">,</span> <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">hasher</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 65 <span class="identifier">key_equal</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">key_equal</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 66 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">allocator_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span> 67 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> 68 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_24-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">InputIterator</span><span class="special">,</span> <span class="identifier">InputIterator</span><span class="special">,</span> 69 <span class="identifier">size_type</span> <span class="special">=</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span><span class="special">,</span> 70 <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">hasher</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> <span class="identifier">key_equal</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">key_equal</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 71 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">allocator_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span> 72 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_25-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">unordered_map</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 73 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_26-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">unordered_map</span> <span class="special">&&</span><span class="special">)</span><span class="special">;</span> 74 <span class="keyword">explicit</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_27-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">Allocator</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 75 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_28-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">unordered_map</span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> <span class="identifier">Allocator</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 76 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_29-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">unordered_map</span> <span class="special">&&</span><span class="special">,</span> <span class="identifier">Allocator</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 77 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_30-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span><span class="special">,</span> 78 <span class="identifier">size_type</span> <span class="special">=</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span><span class="special">,</span> <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">hasher</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 79 <span class="identifier">key_equal</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">key_equal</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 80 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">=</span> <span class="identifier">allocator_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span> 81 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_31-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">,</span> <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 82 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_32-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">,</span> <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 83 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> 84 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_33-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">InputIterator</span><span class="special">,</span> <span class="identifier">InputIterator</span><span class="special">,</span> <span class="identifier">size_type</span><span class="special">,</span> 85 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 86 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> 87 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_34-bb"><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="identifier">InputIterator</span><span class="special">,</span> <span class="identifier">InputIterator</span><span class="special">,</span> <span class="identifier">size_type</span><span class="special">,</span> <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> 88 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 89 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_35-bb"><span class="special">~</span><span class="identifier">unordered_map</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 90 <span class="identifier">unordered_map</span><span class="special">&</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_36-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><span class="identifier">unordered_map</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 91 <span class="identifier">unordered_map</span><span class="special">&</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_37-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><span class="identifier">unordered_map</span> <span class="special">&&</span><span class="special">)</span><span class="special">;</span> 92 <span class="identifier">unordered_map</span><span class="special">&</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_38-bb"><span class="keyword">operator</span><span class="special">=</span></a><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span><span class="special">)</span><span class="special">;</span> 93 <span class="identifier">allocator_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_39-bb"><span class="identifier">get_allocator</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 94 95 <span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40-bb">size and capacity</a></span> 96 <span class="keyword">bool</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_1-bb"><span class="identifier">empty</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 97 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb"><span class="identifier">size</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 98 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_3-bb"><span class="identifier">max_size</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 99 100 <span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41-bb">iterators</a></span> 101 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_1_1-bb"><span class="identifier">begin</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 102 <span class="identifier">const_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_1_2-bb"><span class="identifier">begin</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 103 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_2_1-bb"><span class="identifier">end</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 104 <span class="identifier">const_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_2_2-bb"><span class="identifier">end</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 105 <span class="identifier">const_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_3-bb"><span class="identifier">cbegin</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 106 <span class="identifier">const_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_4-bb"><span class="identifier">cend</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 107 108 <span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42-bb">modifiers</a></span> 109 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span><span class="special">...</span> Args<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="keyword">bool</span><span class="special">></span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_1-bb"><span class="identifier">emplace</span></a><span class="special">(</span><span class="identifier">Args</span><span class="special">&&</span><span class="special">...</span><span class="special">)</span><span class="special">;</span> 110 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span><span class="special">...</span> Args<span class="special">></span> <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_2-bb"><span class="identifier">emplace_hint</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&</span><span class="special">...</span><span class="special">)</span><span class="special">;</span> 111 <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> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_3-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">value_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 112 <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> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_4-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">value_type</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 113 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_5-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">value_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 114 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_6-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">value_type</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 115 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_7-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">InputIterator</span><span class="special">,</span> <span class="identifier">InputIterator</span><span class="special">)</span><span class="special">;</span> 116 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_8-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span><span class="special">)</span><span class="special">;</span> 117 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_9-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span><span class="special">)</span><span class="special">;</span> 118 <span class="identifier">node_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_10-bb"><span class="identifier">extract</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">)</span><span class="special">;</span> 119 <span class="identifier">node_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_11-bb"><span class="identifier">extract</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 120 <span class="identifier">insert_return_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_12-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">node_type</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 121 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_13-bb"><span class="identifier">insert</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">node_type</span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 122 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_14-bb"><span class="identifier">erase</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">)</span><span class="special">;</span> 123 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_15-bb"><span class="identifier">erase</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 124 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_16-bb"><span class="identifier">erase</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">const_iterator</span><span class="special">)</span><span class="special">;</span> 125 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_17-bb"><span class="identifier">quick_erase</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">)</span><span class="special">;</span> 126 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_18-bb"><span class="identifier">erase_return_void</span></a><span class="special">(</span><span class="identifier">const_iterator</span><span class="special">)</span><span class="special">;</span> 127 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_19-bb"><span class="identifier">clear</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 128 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_20-bb"><span class="identifier">swap</span></a><span class="special">(</span><span class="identifier">unordered_map</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 129 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> H2<span class="special">,</span> <span class="keyword">typename</span> P2<span class="special">></span> 130 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_21-bb"><span class="identifier">merge</span></a><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">H2</span><span class="special">,</span> <span class="identifier">P2</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 131 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> H2<span class="special">,</span> <span class="keyword">typename</span> P2<span class="special">></span> 132 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_42_22-bb"><span class="identifier">merge</span></a><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">H2</span><span class="special">,</span> <span class="identifier">P2</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&&</span><span class="special">)</span><span class="special">;</span> 133 134 <span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_43-bb">observers</a></span> 135 <span class="identifier">hasher</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_43_1-bb"><span class="identifier">hash_function</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 136 <span class="identifier">key_equal</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_43_2-bb"><span class="identifier">key_eq</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 137 138 <span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44-bb">lookup</a></span> 139 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_1_1-bb"><span class="identifier">find</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 140 <span class="identifier">const_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_1_2-bb"><span class="identifier">find</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 141 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> CompatibleKey<span class="special">,</span> <span class="keyword">typename</span> CompatibleHash<span class="special">,</span> 142 <span class="keyword">typename</span> CompatiblePredicate<span class="special">></span> 143 <span class="identifier">iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_1_3-bb"><span class="identifier">find</span></a><span class="special">(</span><span class="identifier">CompatibleKey</span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> <span class="identifier">CompatibleHash</span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> 144 <span class="identifier">CompatiblePredicate</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 145 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> CompatibleKey<span class="special">,</span> <span class="keyword">typename</span> CompatibleHash<span class="special">,</span> 146 <span class="keyword">typename</span> CompatiblePredicate<span class="special">></span> 147 <span class="identifier">const_iterator</span> 148 <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_1_4-bb"><span class="identifier">find</span></a><span class="special">(</span><span class="identifier">CompatibleKey</span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> <span class="identifier">CompatibleHash</span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> 149 <span class="identifier">CompatiblePredicate</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 150 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_2-bb"><span class="identifier">count</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 151 <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> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_3_1-bb"><span class="identifier">equal_range</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 152 <span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">const_iterator</span><span class="special">></span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_3_2-bb"><span class="identifier">equal_range</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 153 <span class="identifier">mapped_type</span><span class="special">&</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_4-bb"><span class="keyword">operator</span><span class="special">[</span><span class="special">]</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 154 <span class="identifier">Mapped</span><span class="special">&</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_5_1-bb"><span class="identifier">at</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 155 <span class="identifier">Mapped</span> <span class="keyword">const</span><span class="special">&</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_44_5_2-bb"><span class="identifier">at</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 156 157 <span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45-bb">bucket interface</a></span> 158 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_1-bb"><span class="identifier">bucket_count</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 159 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_2-bb"><span class="identifier">max_bucket_count</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 160 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_3-bb"><span class="identifier">bucket_size</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 161 <span class="identifier">size_type</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_4-bb"><span class="identifier">bucket</span></a><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 162 <span class="identifier">local_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_5_1-bb"><span class="identifier">begin</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span><span class="special">;</span> 163 <span class="identifier">const_local_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_5_2-bb"><span class="identifier">begin</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 164 <span class="identifier">local_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_6_1-bb"><span class="identifier">end</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span><span class="special">;</span> 165 <span class="identifier">const_local_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_6_2-bb"><span class="identifier">end</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 166 <span class="identifier">const_local_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_7-bb"><span class="identifier">cbegin</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 167 <span class="identifier">const_local_iterator</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_8-bb"><span class="identifier">cend</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span><span class="special">;</span> 168 169 <span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_46-bb">hash policy</a></span> 170 <span class="keyword">float</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_46_1-bb"><span class="identifier">load_factor</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 171 <span class="keyword">float</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_46_2-bb"><span class="identifier">max_load_factor</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 172 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_46_3-bb"><span class="identifier">max_load_factor</span></a><span class="special">(</span><span class="keyword">float</span><span class="special">)</span><span class="special">;</span> 173 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_46_4-bb"><span class="identifier">rehash</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span><span class="special">;</span> 174 <span class="keyword">void</span> <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_46_5-bb"><span class="identifier">reserve</span></a><span class="special">(</span><span class="identifier">size_type</span><span class="special">)</span><span class="special">;</span> 175<span class="special">}</span><span class="special">;</span> 176 177<span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_47-bb">Equality Comparisons</a></span> 178<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Mapped<span class="special">,</span> <span class="keyword">typename</span> Hash<span class="special">,</span> <span class="keyword">typename</span> Pred<span class="special">,</span> 179 <span class="keyword">typename</span> Alloc<span class="special">></span> 180 <span class="keyword">bool</span> <a class="link" href="unordered_map.html#boost.unordered_map.operator=="><span class="keyword">operator</span><span class="special">==</span></a><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> 181 <span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 182<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Mapped<span class="special">,</span> <span class="keyword">typename</span> Hash<span class="special">,</span> <span class="keyword">typename</span> Pred<span class="special">,</span> 183 <span class="keyword">typename</span> Alloc<span class="special">></span> 184 <span class="keyword">bool</span> <a class="link" href="unordered_map.html#boost.unordered_map.operator!="><span class="keyword">operator</span><span class="special">!=</span></a><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span><span class="special">,</span> 185 <span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span> 186 187<span class="comment">// <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_48-bb">swap</a></span> 188<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Mapped<span class="special">,</span> <span class="keyword">typename</span> Hash<span class="special">,</span> <span class="keyword">typename</span> Pred<span class="special">,</span> 189 <span class="keyword">typename</span> Alloc<span class="special">></span> 190 <span class="keyword">void</span> <a class="link" href="unordered_map.html#boost.unordered_map.swap"><span class="identifier">swap</span></a><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&</span><span class="special">,</span> 191 <span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&</span><span class="special">)</span><span class="special">;</span></pre></div> 192<div class="refsect1"> 193<a name="id-1.3.45.10.3.4.4"></a><h2>Description</h2> 194<p><span class="bold"><strong>Template Parameters</strong></span> 195 </p> 196<div class="informaltable"><table class="table"> 197<colgroup> 198<col> 199<col> 200</colgroup> 201<tbody> 202<tr> 203<td><span class="emphasis"><em>Key</em></span></td> 204<td> 205<code class="computeroutput">Key</code> must be <code class="computeroutput">Erasable</code> from the container 206 (i.e. <code class="computeroutput">allocator_traits</code> can <code class="computeroutput">destroy</code> it). 207 </td> 208</tr> 209<tr> 210<td><span class="emphasis"><em>Mapped</em></span></td> 211<td> 212<code class="computeroutput">Mapped</code> must be <code class="computeroutput">Erasable</code> from the container 213 (i.e. <code class="computeroutput">allocator_traits</code> can <code class="computeroutput">destroy</code> it). 214 </td> 215</tr> 216<tr> 217<td><span class="emphasis"><em>Hash</em></span></td> 218<td>A unary function object type that acts a hash function for a <code class="computeroutput">Key</code>. It takes a single argument of type <code class="computeroutput">Key</code> and returns a value of type std::size_t.</td> 219</tr> 220<tr> 221<td><span class="emphasis"><em>Pred</em></span></td> 222<td>A binary function object that implements an equivalence relation on values of type <code class="computeroutput">Key</code>. 223 A binary function object that induces an equivalence relation on values of type <code class="computeroutput">Key</code>. 224 It takes two arguments of type <code class="computeroutput">Key</code> and returns a value of type bool.</td> 225</tr> 226<tr> 227<td><span class="emphasis"><em>Alloc</em></span></td> 228<td>An allocator whose value type is the same as the container's value type.</td> 229</tr> 230</tbody> 231</table></div> 232<p>The elements are organized into buckets. Keys with the same hash code are stored in the same bucket.</p> 233<p>The number of buckets can be automatically increased by a call to insert, or as the result of calling rehash.</p> 234<div class="refsect2"> 235<a name="id-1.3.45.10.3.4.4.5"></a><h3> 236<a name="boost.unordered_maptypes"></a><code class="computeroutput">unordered_map</code> 237 public 238 types</h3> 239<div class="orderedlist"><ol class="orderedlist" type="1"> 240<li class="listitem"> 241<p> 242<span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">allocator_type</span><span class="special">::</span><span class="identifier">pointer</span> <a name="boost.unordered_map.pointer"></a><span class="identifier">pointer</span><span class="special">;</span></p> 243<p> 244 <code class="computeroutput">value_type*</code> if 245 <code class="computeroutput">allocator_type::pointer</code> is not defined. 246 </p> 247</li> 248<li class="listitem"> 249<p> 250<span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">allocator_type</span><span class="special">::</span><span class="identifier">const_pointer</span> <a name="boost.unordered_map.const_pointer"></a><span class="identifier">const_pointer</span><span class="special">;</span></p> 251<p> 252 <code class="computeroutput">boost::pointer_to_other<pointer, value_type>::type</code> 253 if <code class="computeroutput">allocator_type::const_pointer</code> is not defined. 254 </p> 255</li> 256<li class="listitem"> 257<p> 258<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.size_type"></a><span class="identifier">size_type</span><span class="special">;</span></p> 259<p>An unsigned integral type.</p> 260<p>size_type can represent any non-negative value of difference_type.</p> 261</li> 262<li class="listitem"> 263<p> 264<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.difference_type"></a><span class="identifier">difference_type</span><span class="special">;</span></p> 265<p>A signed integral type.</p> 266<p>Is identical to the difference type of iterator and const_iterator.</p> 267</li> 268<li class="listitem"> 269<p> 270<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.iterator"></a><span class="identifier">iterator</span><span class="special">;</span></p> 271<p>An iterator whose value type is value_type. </p> 272<p>The iterator category is at least a forward iterator.</p> 273<p>Convertible to const_iterator.</p> 274</li> 275<li class="listitem"> 276<p> 277<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.const_iterator"></a><span class="identifier">const_iterator</span><span class="special">;</span></p> 278<p>A constant iterator whose value type is value_type. </p> 279<p>The iterator category is at least a forward iterator.</p> 280</li> 281<li class="listitem"> 282<p> 283<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.local_iterator"></a><span class="identifier">local_iterator</span><span class="special">;</span></p> 284<p>An iterator with the same value type, difference type and pointer and reference type as iterator.</p> 285<p>A local_iterator object can be used to iterate through a single bucket.</p> 286</li> 287<li class="listitem"> 288<p> 289<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.const_local_iterator"></a><span class="identifier">const_local_iterator</span><span class="special">;</span></p> 290<p>A constant iterator with the same value type, difference type and pointer and reference type as const_iterator.</p> 291<p>A const_local_iterator object can be used to iterate through a single bucket.</p> 292</li> 293<li class="listitem"> 294<p> 295<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.node_type"></a><span class="identifier">node_type</span><span class="special">;</span></p> 296<p>See node_handle_map for details.</p> 297</li> 298<li class="listitem"> 299<p> 300<span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span> <a name="boost.unordered_map.insert_return_type"></a><span class="identifier">insert_return_type</span><span class="special">;</span></p> 301 Structure returned by inserting <code class="computeroutput">node_type</code>. 302 </li> 303</ol></div> 304</div> 305<div class="refsect2"> 306<a name="id-1.3.45.10.3.4.4.6"></a><h3> 307<a name="boost.unordered_mapconstruct-copy-destruct"></a><code class="computeroutput">unordered_map</code> 308 public 309 construct/copy/destruct</h3> 310<div class="orderedlist"><ol class="orderedlist" type="1"> 311<li class="listitem"> 312<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_22-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 313<p>Constructs an empty container using hasher() as the hash function, key_equal() as the key equality predicate, allocator_type() as the allocator and a maximum load factor of 1.0.</p> 314<div class="variablelist"><table border="0" class="variablelist compact"> 315<colgroup> 316<col align="left" valign="top"> 317<col> 318</colgroup> 319<tbody> 320<tr> 321<td><p><span class="term">Postconditions:</span></p></td> 322<td><code class="computeroutput"><a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb">size</a>() == 0</code></td> 323</tr> 324<tr> 325<td><p><span class="term">Requires:</span></p></td> 326<td><p>If the defaults are used, <code class="computeroutput">hasher</code>, <code class="computeroutput">key_equal</code> and 327 <code class="computeroutput">allocator_type</code> need to be <code class="computeroutput">DefaultConstructible</code>. 328 </p></td> 329</tr> 330</tbody> 331</table></div> 332</li> 333<li class="listitem"> 334<pre class="literallayout"><span class="keyword">explicit</span> <a name="id-1_3_45_10_2_1_1_23-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">,</span> <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> hf <span class="special">=</span> <span class="identifier">hasher</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 335 <span class="identifier">key_equal</span> <span class="keyword">const</span><span class="special">&</span> eq <span class="special">=</span> <span class="identifier">key_equal</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 336 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> a <span class="special">=</span> <span class="identifier">allocator_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span></pre> 337<p>Constructs an empty container with at least n buckets, using hf as the hash function, eq as the key equality predicate, a as the allocator and a maximum load factor of 1.0.</p> 338<div class="variablelist"><table border="0" class="variablelist compact"> 339<colgroup> 340<col align="left" valign="top"> 341<col> 342</colgroup> 343<tbody> 344<tr> 345<td><p><span class="term">Postconditions:</span></p></td> 346<td><code class="computeroutput"><a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb">size</a>() == 0</code></td> 347</tr> 348<tr> 349<td><p><span class="term">Requires:</span></p></td> 350<td><p>If the defaults are used, <code class="computeroutput">hasher</code>, <code class="computeroutput">key_equal</code> and 351 <code class="computeroutput">allocator_type</code> need to be <code class="computeroutput">DefaultConstructible</code>. 352 </p></td> 353</tr> 354</tbody> 355</table></div> 356</li> 357<li class="listitem"> 358<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> 359 <a name="id-1_3_45_10_2_1_1_24-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">InputIterator</span> f<span class="special">,</span> <span class="identifier">InputIterator</span> l<span class="special">,</span> 360 <span class="identifier">size_type</span> n <span class="special">=</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span><span class="special">,</span> 361 <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> hf <span class="special">=</span> <span class="identifier">hasher</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 362 <span class="identifier">key_equal</span> <span class="keyword">const</span><span class="special">&</span> eq <span class="special">=</span> <span class="identifier">key_equal</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 363 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> a <span class="special">=</span> <span class="identifier">allocator_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span></pre> 364<p>Constructs an empty container with at least <code class="computeroutput">n</code> buckets, 365 using <code class="computeroutput">hf</code> as the hash function, 366 <code class="computeroutput">eq</code> as the key equality predicate, 367 <code class="computeroutput">a</code> as the allocator and a maximum load factor of 1.0 368 and inserts the elements from [f, l) into it. 369 </p> 370<div class="variablelist"><table border="0" class="variablelist compact"> 371<colgroup> 372<col align="left" valign="top"> 373<col> 374</colgroup> 375<tbody><tr> 376<td><p><span class="term">Requires:</span></p></td> 377<td><p>If the defaults are used, <code class="computeroutput">hasher</code>, <code class="computeroutput">key_equal</code> and 378 <code class="computeroutput">allocator_type</code> need to be <code class="computeroutput">DefaultConstructible</code>. 379 </p></td> 380</tr></tbody> 381</table></div> 382</li> 383<li class="listitem"> 384<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_25-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">unordered_map</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span></pre> 385<p>The copy constructor. Copies the contained elements, hash function, predicate, maximum load factor and allocator.</p> 386<p>If <code class="computeroutput">Allocator::select_on_container_copy_construction</code> 387 exists and has the right signature, the allocator will be 388 constructed from its result.</p> 389<div class="variablelist"><table border="0" class="variablelist compact"> 390<colgroup> 391<col align="left" valign="top"> 392<col> 393</colgroup> 394<tbody><tr> 395<td><p><span class="term">Requires:</span></p></td> 396<td><p><code class="computeroutput">value_type</code> is copy constructible</p></td> 397</tr></tbody> 398</table></div> 399</li> 400<li class="listitem"> 401<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_26-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">unordered_map</span> <span class="special">&&</span><span class="special">)</span><span class="special">;</span></pre> 402<p>The move constructor.</p> 403<div class="variablelist"><table border="0" class="variablelist compact"> 404<colgroup> 405<col align="left" valign="top"> 406<col> 407</colgroup> 408<tbody> 409<tr> 410<td><p><span class="term">Notes:</span></p></td> 411<td><p>This is implemented using Boost.Move.</p></td> 412</tr> 413<tr> 414<td><p><span class="term">Requires:</span></p></td> 415<td> 416<p> 417 <code class="computeroutput">value_type</code> is move constructible. 418 </p> 419<p> 420 On compilers without rvalue reference support the 421 emulation does not support moving without calling 422 <code class="computeroutput">boost::move</code> if <code class="computeroutput">value_type</code> is 423 not copyable. So, for example, you can't return the 424 container from a function. 425 </p> 426</td> 427</tr> 428</tbody> 429</table></div> 430</li> 431<li class="listitem"> 432<pre class="literallayout"><span class="keyword">explicit</span> <a name="id-1_3_45_10_2_1_1_27-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">Allocator</span> <span class="keyword">const</span><span class="special">&</span> a<span class="special">)</span><span class="special">;</span></pre> 433<p>Constructs an empty container, using allocator <code class="computeroutput">a</code>.</p> 434</li> 435<li class="listitem"> 436<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_28-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">unordered_map</span> <span class="keyword">const</span><span class="special">&</span> x<span class="special">,</span> <span class="identifier">Allocator</span> <span class="keyword">const</span><span class="special">&</span> a<span class="special">)</span><span class="special">;</span></pre> 437<p>Constructs an container, copying <code class="computeroutput">x</code>'s contained elements, hash function, predicate, maximum load factor, but using allocator <code class="computeroutput">a</code>.</p> 438</li> 439<li class="listitem"> 440<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_29-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">unordered_map</span> <span class="special">&&</span> x<span class="special">,</span> <span class="identifier">Allocator</span> <span class="keyword">const</span><span class="special">&</span> a<span class="special">)</span><span class="special">;</span></pre> 441<p>Construct a container moving <code class="computeroutput">x</code>'s contained elements, and having the hash function, predicate and maximum load factor, but using allocate <code class="computeroutput">a</code>.</p> 442<div class="variablelist"><table border="0" class="variablelist compact"> 443<colgroup> 444<col align="left" valign="top"> 445<col> 446</colgroup> 447<tbody> 448<tr> 449<td><p><span class="term">Notes:</span></p></td> 450<td><p>This is implemented using Boost.Move.</p></td> 451</tr> 452<tr> 453<td><p><span class="term">Requires:</span></p></td> 454<td><p> 455 <code class="computeroutput">value_type</code> is move insertable. 456 </p></td> 457</tr> 458</tbody> 459</table></div> 460</li> 461<li class="listitem"> 462<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_30-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span> il<span class="special">,</span> 463 <span class="identifier">size_type</span> n <span class="special">=</span> <span class="emphasis"><em><span class="identifier">implementation</span><span class="special">-</span><span class="identifier">defined</span></em></span><span class="special">,</span> 464 <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> hf <span class="special">=</span> <span class="identifier">hasher</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> <span class="identifier">key_equal</span> <span class="keyword">const</span><span class="special">&</span> eq <span class="special">=</span> <span class="identifier">key_equal</span><span class="special">(</span><span class="special">)</span><span class="special">,</span> 465 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> a <span class="special">=</span> <span class="identifier">allocator_type</span><span class="special">(</span><span class="special">)</span><span class="special">)</span><span class="special">;</span></pre> 466<p>Constructs an empty container with at least <code class="computeroutput">n</code> buckets, 467 using <code class="computeroutput">hf</code> as the hash function, 468 <code class="computeroutput">eq</code> as the key equality predicate, 469 <code class="computeroutput">a</code> as the allocator and a maximum load factor of 1.0 470 and inserts the elements from <code class="computeroutput">il</code> into it. 471 </p> 472<div class="variablelist"><table border="0" class="variablelist compact"> 473<colgroup> 474<col align="left" valign="top"> 475<col> 476</colgroup> 477<tbody><tr> 478<td><p><span class="term">Requires:</span></p></td> 479<td><p>If the defaults are used, <code class="computeroutput">hasher</code>, <code class="computeroutput">key_equal</code> and 480 <code class="computeroutput">allocator_type</code> need to be <code class="computeroutput">DefaultConstructible</code>. 481 </p></td> 482</tr></tbody> 483</table></div> 484</li> 485<li class="listitem"> 486<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_31-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">,</span> <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> a<span class="special">)</span><span class="special">;</span></pre> 487<p>Constructs an empty container with at least <code class="computeroutput">n</code> buckets, 488 using <code class="computeroutput">hf</code> as the hash function, 489 the default hash function and key equality predicate, 490 <code class="computeroutput">a</code> as the allocator and a maximum load factor of 1.0.</p> 491<div class="variablelist"><table border="0" class="variablelist compact"> 492<colgroup> 493<col align="left" valign="top"> 494<col> 495</colgroup> 496<tbody> 497<tr> 498<td><p><span class="term">Postconditions:</span></p></td> 499<td><code class="computeroutput"><a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb">size</a>() == 0</code></td> 500</tr> 501<tr> 502<td><p><span class="term">Requires:</span></p></td> 503<td><p><code class="computeroutput">hasher</code> and <code class="computeroutput">key_equal</code> need to be <code class="computeroutput">DefaultConstructible</code>. 504 </p></td> 505</tr> 506</tbody> 507</table></div> 508</li> 509<li class="listitem"> 510<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_32-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">,</span> <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> hf<span class="special">,</span> <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> a<span class="special">)</span><span class="special">;</span></pre> 511<p>Constructs an empty container with at least <code class="computeroutput">n</code> buckets, 512 using <code class="computeroutput">hf</code> as the hash function, 513 the default key equality predicate, 514 <code class="computeroutput">a</code> as the allocator and a maximum load factor of 1.0.</p> 515<div class="variablelist"><table border="0" class="variablelist compact"> 516<colgroup> 517<col align="left" valign="top"> 518<col> 519</colgroup> 520<tbody> 521<tr> 522<td><p><span class="term">Postconditions:</span></p></td> 523<td><code class="computeroutput"><a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb">size</a>() == 0</code></td> 524</tr> 525<tr> 526<td><p><span class="term">Requires:</span></p></td> 527<td><p><code class="computeroutput">key_equal</code> needs to be <code class="computeroutput">DefaultConstructible</code>. 528 </p></td> 529</tr> 530</tbody> 531</table></div> 532</li> 533<li class="listitem"> 534<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> 535 <a name="id-1_3_45_10_2_1_1_33-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">InputIterator</span> f<span class="special">,</span> <span class="identifier">InputIterator</span> l<span class="special">,</span> <span class="identifier">size_type</span> n<span class="special">,</span> 536 <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> a<span class="special">)</span><span class="special">;</span></pre> 537<p>Constructs an empty container with at least <code class="computeroutput">n</code> buckets, 538 using <code class="computeroutput">a</code> as the allocator, with the 539 default hash function and key equality predicate 540 and a maximum load factor of 1.0 541 and inserts the elements from [f, l) into it. 542 </p> 543<div class="variablelist"><table border="0" class="variablelist compact"> 544<colgroup> 545<col align="left" valign="top"> 546<col> 547</colgroup> 548<tbody><tr> 549<td><p><span class="term">Requires:</span></p></td> 550<td><p><code class="computeroutput">hasher</code>, <code class="computeroutput">key_equal</code> need to be <code class="computeroutput">DefaultConstructible</code>. 551 </p></td> 552</tr></tbody> 553</table></div> 554</li> 555<li class="listitem"> 556<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> 557 <a name="id-1_3_45_10_2_1_1_34-bb"></a><span class="identifier">unordered_map</span><span class="special">(</span><span class="identifier">InputIterator</span> f<span class="special">,</span> <span class="identifier">InputIterator</span> l<span class="special">,</span> <span class="identifier">size_type</span> n<span class="special">,</span> 558 <span class="identifier">hasher</span> <span class="keyword">const</span><span class="special">&</span> hf<span class="special">,</span> <span class="identifier">allocator_type</span> <span class="keyword">const</span><span class="special">&</span> a<span class="special">)</span><span class="special">;</span></pre> 559<p>Constructs an empty container with at least <code class="computeroutput">n</code> buckets, 560 using <code class="computeroutput">hf</code> as the hash function, 561 <code class="computeroutput">a</code> as the allocator, with the 562 default key equality predicate 563 and a maximum load factor of 1.0 564 and inserts the elements from [f, l) into it. 565 </p> 566<div class="variablelist"><table border="0" class="variablelist compact"> 567<colgroup> 568<col align="left" valign="top"> 569<col> 570</colgroup> 571<tbody><tr> 572<td><p><span class="term">Requires:</span></p></td> 573<td><p><code class="computeroutput">key_equal</code> needs to be <code class="computeroutput">DefaultConstructible</code>. 574 </p></td> 575</tr></tbody> 576</table></div> 577</li> 578<li class="listitem"> 579<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_35-bb"></a><span class="special">~</span><span class="identifier">unordered_map</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 580<div class="variablelist"><table border="0" class="variablelist compact"> 581<colgroup> 582<col align="left" valign="top"> 583<col> 584</colgroup> 585<tbody><tr> 586<td><p><span class="term">Notes:</span></p></td> 587<td><p>The destructor is applied to every element, and all memory is deallocated</p></td> 588</tr></tbody> 589</table></div> 590</li> 591</ol></div> 592</div> 593<pre class="literallayout"><span class="identifier">unordered_map</span><span class="special">&</span> <a name="id-1_3_45_10_2_1_1_36-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><span class="identifier">unordered_map</span> <span class="keyword">const</span><span class="special">&</span><span class="special">)</span><span class="special">;</span></pre> 594<p>The assignment operator. Copies the contained elements, hash function, predicate and maximum load factor but not the allocator.</p> 595<p>If <code class="computeroutput">Alloc::propagate_on_container_copy_assignment</code> 596 exists and <code class="computeroutput">Alloc::propagate_on_container_copy_assignment::value 597 </code> is true, the allocator is overwritten, if not the 598 copied elements are created using the existing 599 allocator.</p> 600<div class="variablelist"><table border="0" class="variablelist compact"> 601<colgroup> 602<col align="left" valign="top"> 603<col> 604</colgroup> 605<tbody><tr> 606<td><p><span class="term">Requires:</span></p></td> 607<td><p><code class="computeroutput">value_type</code> is copy constructible</p></td> 608</tr></tbody> 609</table></div> 610<pre class="literallayout"><span class="identifier">unordered_map</span><span class="special">&</span> <a name="id-1_3_45_10_2_1_1_37-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><span class="identifier">unordered_map</span> <span class="special">&&</span><span class="special">)</span><span class="special">;</span></pre> 611<p>The move assignment operator.</p> 612<p>If <code class="computeroutput">Alloc::propagate_on_container_move_assignment</code> 613 exists and <code class="computeroutput">Alloc::propagate_on_container_move_assignment::value 614 </code> is true, the allocator is overwritten, if not the 615 moved elements are created using the existing 616 allocator.</p> 617<div class="variablelist"><table border="0" class="variablelist compact"> 618<colgroup> 619<col align="left" valign="top"> 620<col> 621</colgroup> 622<tbody> 623<tr> 624<td><p><span class="term">Notes:</span></p></td> 625<td><p> 626 On compilers without rvalue references, this is emulated using 627 Boost.Move. Note that on some compilers the copy assignment 628 operator may be used in some circumstances. 629 </p></td> 630</tr> 631<tr> 632<td><p><span class="term">Requires:</span></p></td> 633<td><p> 634 <code class="computeroutput">value_type</code> is move constructible. 635 </p></td> 636</tr> 637</tbody> 638</table></div> 639<pre class="literallayout"><span class="identifier">unordered_map</span><span class="special">&</span> <a name="id-1_3_45_10_2_1_1_38-bb"></a><span class="keyword">operator</span><span class="special">=</span><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span><span class="special">)</span><span class="special">;</span></pre> 640<p>Assign from values in initializer list. All existing elements are either overwritten by the new elements or destroyed.</p> 641<div class="variablelist"><table border="0" class="variablelist compact"> 642<colgroup> 643<col align="left" valign="top"> 644<col> 645</colgroup> 646<tbody><tr> 647<td><p><span class="term">Requires:</span></p></td> 648<td><p> 649 <code class="computeroutput">value_type</code> is <code class="computeroutput">CopyInsertable</code> into the container and 650 <code class="computeroutput">CopyAssignable</code>. 651 </p></td> 652</tr></tbody> 653</table></div> 654<pre class="literallayout"><span class="identifier">allocator_type</span> <a name="id-1_3_45_10_2_1_1_39-bb"></a><span class="identifier">get_allocator</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 655<div class="refsect2"> 656<a name="id-1.3.45.10.3.4.4.19"></a><h3> 657<a name="id-1_3_45_10_2_1_1_40-bb"></a><code class="computeroutput">unordered_map</code> size and capacity</h3> 658<div class="orderedlist"><ol class="orderedlist" type="1"> 659<li class="listitem"> 660<pre class="literallayout"><span class="keyword">bool</span> <a name="id-1_3_45_10_2_1_1_40_1-bb"></a><span class="identifier">empty</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 661<div class="variablelist"><table border="0" class="variablelist compact"> 662<colgroup> 663<col align="left" valign="top"> 664<col> 665</colgroup> 666<tbody><tr> 667<td><p><span class="term">Returns:</span></p></td> 668<td><code class="computeroutput"><a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb">size</a>() == 0</code></td> 669</tr></tbody> 670</table></div> 671</li> 672<li class="listitem"> 673<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_40_2-bb"></a><span class="identifier">size</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 674<div class="variablelist"><table border="0" class="variablelist compact"> 675<colgroup> 676<col align="left" valign="top"> 677<col> 678</colgroup> 679<tbody><tr> 680<td><p><span class="term">Returns:</span></p></td> 681<td><code class="computeroutput">std::distance(<a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_1-bb">begin</a>(), <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_41_2-bb">end</a>())</code></td> 682</tr></tbody> 683</table></div> 684</li> 685<li class="listitem"> 686<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_40_3-bb"></a><span class="identifier">max_size</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 687<div class="variablelist"><table border="0" class="variablelist compact"> 688<colgroup> 689<col align="left" valign="top"> 690<col> 691</colgroup> 692<tbody><tr> 693<td><p><span class="term">Returns:</span></p></td> 694<td> 695<code class="computeroutput"><a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb">size</a>()</code> of the largest possible container. 696 </td> 697</tr></tbody> 698</table></div> 699</li> 700</ol></div> 701</div> 702<div class="refsect2"> 703<a name="id-1.3.45.10.3.4.4.20"></a><h3> 704<a name="id-1_3_45_10_2_1_1_41-bb"></a><code class="computeroutput">unordered_map</code> iterators</h3> 705<div class="orderedlist"><ol class="orderedlist" type="1"> 706<li class="listitem"> 707<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_41_1-bb"></a><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_41_1_1-bb"></a><span class="identifier">begin</span><span class="special">(</span><span class="special">)</span><span class="special">;</span> 708<span class="identifier">const_iterator</span> <a name="id-1_3_45_10_2_1_1_41_1_2-bb"></a><span class="identifier">begin</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 709<div class="variablelist"><table border="0" class="variablelist compact"> 710<colgroup> 711<col align="left" valign="top"> 712<col> 713</colgroup> 714<tbody><tr> 715<td><p><span class="term">Returns:</span></p></td> 716<td>An iterator referring to the first element of the container, or if the container is empty the past-the-end value for the container. 717 </td> 718</tr></tbody> 719</table></div> 720</li> 721<li class="listitem"> 722<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_41_2-bb"></a><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_41_2_1-bb"></a><span class="identifier">end</span><span class="special">(</span><span class="special">)</span><span class="special">;</span> 723<span class="identifier">const_iterator</span> <a name="id-1_3_45_10_2_1_1_41_2_2-bb"></a><span class="identifier">end</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 724<div class="variablelist"><table border="0" class="variablelist compact"> 725<colgroup> 726<col align="left" valign="top"> 727<col> 728</colgroup> 729<tbody><tr> 730<td><p><span class="term">Returns:</span></p></td> 731<td>An iterator which refers to the past-the-end value for the container. 732 </td> 733</tr></tbody> 734</table></div> 735</li> 736<li class="listitem"> 737<pre class="literallayout"><span class="identifier">const_iterator</span> <a name="id-1_3_45_10_2_1_1_41_3-bb"></a><span class="identifier">cbegin</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 738<div class="variablelist"><table border="0" class="variablelist compact"> 739<colgroup> 740<col align="left" valign="top"> 741<col> 742</colgroup> 743<tbody><tr> 744<td><p><span class="term">Returns:</span></p></td> 745<td>A constant iterator referring to the first element of the container, or if the container is empty the past-the-end value for the container. 746 </td> 747</tr></tbody> 748</table></div> 749</li> 750<li class="listitem"> 751<pre class="literallayout"><span class="identifier">const_iterator</span> <a name="id-1_3_45_10_2_1_1_41_4-bb"></a><span class="identifier">cend</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 752<div class="variablelist"><table border="0" class="variablelist compact"> 753<colgroup> 754<col align="left" valign="top"> 755<col> 756</colgroup> 757<tbody><tr> 758<td><p><span class="term">Returns:</span></p></td> 759<td>A constant iterator which refers to the past-the-end value for the container. 760 </td> 761</tr></tbody> 762</table></div> 763</li> 764</ol></div> 765</div> 766<div class="refsect2"> 767<a name="id-1.3.45.10.3.4.4.21"></a><h3> 768<a name="id-1_3_45_10_2_1_1_42-bb"></a><code class="computeroutput">unordered_map</code> modifiers</h3> 769<div class="orderedlist"><ol class="orderedlist" type="1"> 770<li class="listitem"> 771<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span><span class="special">...</span> Args<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="keyword">bool</span><span class="special">></span> <a name="id-1_3_45_10_2_1_1_42_1-bb"></a><span class="identifier">emplace</span><span class="special">(</span><span class="identifier">Args</span><span class="special">&&</span><span class="special">...</span> args<span class="special">)</span><span class="special">;</span></pre> 772<p>Inserts an object, constructed with the arguments <code class="computeroutput">args</code>, in the container if and only if there is no element in the container with an equivalent key.</p> 773<div class="variablelist"><table border="0" class="variablelist compact"> 774<colgroup> 775<col align="left" valign="top"> 776<col> 777</colgroup> 778<tbody> 779<tr> 780<td><p><span class="term">Requires:</span></p></td> 781<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">EmplaceConstructible</code> into 782 <code class="computeroutput">X</code> from <code class="computeroutput">args</code>. 783 </p></td> 784</tr> 785<tr> 786<td><p><span class="term">Returns:</span></p></td> 787<td> 788<p>The bool component of the return type is true if an insert took place.</p> 789<p>If an insert took place, then the iterator points to the newly inserted element. Otherwise, it points to the element with equivalent key.</p> 790</td> 791</tr> 792<tr> 793<td><p><span class="term">Throws:</span></p></td> 794<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 795</tr> 796<tr> 797<td><p><span class="term">Notes:</span></p></td> 798<td> 799<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 800<p>Pointers and references to elements are never invalidated.</p> 801<p>If the compiler doesn't support variadic template arguments or rvalue 802 references, this is emulated for up to 10 arguments, with no support 803 for rvalue references or move semantics.</p> 804<p>Since existing <code class="computeroutput">std::pair</code> implementations don't support 805 <code class="computeroutput">std::piecewise_construct</code> this emulates it, 806 but using <code class="computeroutput">boost::unordered::piecewise_construct</code>.</p> 807</td> 808</tr> 809</tbody> 810</table></div> 811</li> 812<li class="listitem"> 813<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span><span class="special">...</span> Args<span class="special">></span> 814 <span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_42_2-bb"></a><span class="identifier">emplace_hint</span><span class="special">(</span><span class="identifier">const_iterator</span> hint<span class="special">,</span> <span class="identifier">Args</span><span class="special">&&</span><span class="special">...</span> args<span class="special">)</span><span class="special">;</span></pre> 815<p>Inserts an object, constructed with the arguments <code class="computeroutput">args</code>, in the container if and only if there is no element in the container with an equivalent key.</p> 816<p><code class="computeroutput">hint</code> is a suggestion to where the element should be inserted.</p> 817<div class="variablelist"><table border="0" class="variablelist compact"> 818<colgroup> 819<col align="left" valign="top"> 820<col> 821</colgroup> 822<tbody> 823<tr> 824<td><p><span class="term">Requires:</span></p></td> 825<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">EmplaceConstructible</code> into 826 <code class="computeroutput">X</code> from <code class="computeroutput">args</code>. 827 </p></td> 828</tr> 829<tr> 830<td><p><span class="term">Returns:</span></p></td> 831<td><p>If an insert took place, then the iterator points to the newly inserted element. Otherwise, it points to the element with equivalent key.</p></td> 832</tr> 833<tr> 834<td><p><span class="term">Throws:</span></p></td> 835<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 836</tr> 837<tr> 838<td><p><span class="term">Notes:</span></p></td> 839<td> 840<p>The standard is fairly vague on the meaning of the hint. But the only practical way to use it, and the only way that Boost.Unordered supports is to point to an existing element with the same key. </p> 841<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 842<p>Pointers and references to elements are never invalidated.</p> 843<p>If the compiler doesn't support variadic template arguments or rvalue 844 references, this is emulated for up to 10 arguments, with no support 845 for rvalue references or move semantics.</p> 846<p>Since existing <code class="computeroutput">std::pair</code> implementations don't support 847 <code class="computeroutput">std::piecewise_construct</code> this emulates it, 848 but using <code class="computeroutput">boost::unordered::piecewise_construct</code>.</p> 849</td> 850</tr> 851</tbody> 852</table></div> 853</li> 854<li class="listitem"> 855<pre class="literallayout"><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> <a name="id-1_3_45_10_2_1_1_42_3-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">value_type</span> <span class="keyword">const</span><span class="special">&</span> obj<span class="special">)</span><span class="special">;</span></pre> 856<p>Inserts <code class="computeroutput">obj</code> in the container if and only if there is no element in the container with an equivalent key.</p> 857<div class="variablelist"><table border="0" class="variablelist compact"> 858<colgroup> 859<col align="left" valign="top"> 860<col> 861</colgroup> 862<tbody> 863<tr> 864<td><p><span class="term">Requires:</span></p></td> 865<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">CopyInsertable</code>.</p></td> 866</tr> 867<tr> 868<td><p><span class="term">Returns:</span></p></td> 869<td> 870<p>The bool component of the return type is true if an insert took place.</p> 871<p>If an insert took place, then the iterator points to the newly inserted element. Otherwise, it points to the element with equivalent key.</p> 872</td> 873</tr> 874<tr> 875<td><p><span class="term">Throws:</span></p></td> 876<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 877</tr> 878<tr> 879<td><p><span class="term">Notes:</span></p></td> 880<td> 881<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 882<p>Pointers and references to elements are never invalidated.</p> 883</td> 884</tr> 885</tbody> 886</table></div> 887</li> 888<li class="listitem"> 889<pre class="literallayout"><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> <a name="id-1_3_45_10_2_1_1_42_4-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">value_type</span><span class="special">&&</span> obj<span class="special">)</span><span class="special">;</span></pre> 890<p>Inserts <code class="computeroutput">obj</code> in the container if and only if there is no element in the container with an equivalent key.</p> 891<div class="variablelist"><table border="0" class="variablelist compact"> 892<colgroup> 893<col align="left" valign="top"> 894<col> 895</colgroup> 896<tbody> 897<tr> 898<td><p><span class="term">Requires:</span></p></td> 899<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">MoveInsertable</code>.</p></td> 900</tr> 901<tr> 902<td><p><span class="term">Returns:</span></p></td> 903<td> 904<p>The bool component of the return type is true if an insert took place.</p> 905<p>If an insert took place, then the iterator points to the newly inserted element. Otherwise, it points to the element with equivalent key.</p> 906</td> 907</tr> 908<tr> 909<td><p><span class="term">Throws:</span></p></td> 910<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 911</tr> 912<tr> 913<td><p><span class="term">Notes:</span></p></td> 914<td> 915<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 916<p>Pointers and references to elements are never invalidated.</p> 917</td> 918</tr> 919</tbody> 920</table></div> 921</li> 922<li class="listitem"> 923<pre class="literallayout"><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_42_5-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">const_iterator</span> hint<span class="special">,</span> <span class="identifier">value_type</span> <span class="keyword">const</span><span class="special">&</span> obj<span class="special">)</span><span class="special">;</span></pre> 924<p>Inserts <code class="computeroutput">obj</code> in the container if and only if there is no element in the container with an equivalent key.</p> 925<p>hint is a suggestion to where the element should be inserted.</p> 926<div class="variablelist"><table border="0" class="variablelist compact"> 927<colgroup> 928<col align="left" valign="top"> 929<col> 930</colgroup> 931<tbody> 932<tr> 933<td><p><span class="term">Requires:</span></p></td> 934<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">CopyInsertable</code>.</p></td> 935</tr> 936<tr> 937<td><p><span class="term">Returns:</span></p></td> 938<td><p>If an insert took place, then the iterator points to the newly inserted element. Otherwise, it points to the element with equivalent key.</p></td> 939</tr> 940<tr> 941<td><p><span class="term">Throws:</span></p></td> 942<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 943</tr> 944<tr> 945<td><p><span class="term">Notes:</span></p></td> 946<td> 947<p>The standard is fairly vague on the meaning of the hint. But the only practical way to use it, and the only way that Boost.Unordered supports is to point to an existing element with the same key. </p> 948<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 949<p>Pointers and references to elements are never invalidated.</p> 950</td> 951</tr> 952</tbody> 953</table></div> 954</li> 955<li class="listitem"> 956<pre class="literallayout"><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_42_6-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">const_iterator</span> hint<span class="special">,</span> <span class="identifier">value_type</span><span class="special">&&</span> obj<span class="special">)</span><span class="special">;</span></pre> 957<p>Inserts <code class="computeroutput">obj</code> in the container if and only if there is no element in the container with an equivalent key.</p> 958<p>hint is a suggestion to where the element should be inserted.</p> 959<div class="variablelist"><table border="0" class="variablelist compact"> 960<colgroup> 961<col align="left" valign="top"> 962<col> 963</colgroup> 964<tbody> 965<tr> 966<td><p><span class="term">Requires:</span></p></td> 967<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">MoveInsertable</code>.</p></td> 968</tr> 969<tr> 970<td><p><span class="term">Returns:</span></p></td> 971<td><p>If an insert took place, then the iterator points to the newly inserted element. Otherwise, it points to the element with equivalent key.</p></td> 972</tr> 973<tr> 974<td><p><span class="term">Throws:</span></p></td> 975<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 976</tr> 977<tr> 978<td><p><span class="term">Notes:</span></p></td> 979<td> 980<p>The standard is fairly vague on the meaning of the hint. But the only practical way to use it, and the only way that Boost.Unordered supports is to point to an existing element with the same key. </p> 981<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 982<p>Pointers and references to elements are never invalidated.</p> 983</td> 984</tr> 985</tbody> 986</table></div> 987</li> 988<li class="listitem"> 989<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../InputIterator.html" title="Concept InputIterator">InputIterator</a><span class="special">></span> 990 <span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_42_7-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">InputIterator</span> first<span class="special">,</span> <span class="identifier">InputIterator</span> last<span class="special">)</span><span class="special">;</span></pre> 991<p>Inserts a range of elements into the container. 992 Elements are inserted if and only if there is no element in the container with an equivalent key. 993 </p> 994<div class="variablelist"><table border="0" class="variablelist compact"> 995<colgroup> 996<col align="left" valign="top"> 997<col> 998</colgroup> 999<tbody> 1000<tr> 1001<td><p><span class="term">Requires:</span></p></td> 1002<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">EmplaceConstructible</code> into 1003 <code class="computeroutput">X</code> from <code class="computeroutput">*first</code>.</p></td> 1004</tr> 1005<tr> 1006<td><p><span class="term">Throws:</span></p></td> 1007<td><p>When inserting a single element, if an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 1008</tr> 1009<tr> 1010<td><p><span class="term">Notes:</span></p></td> 1011<td> 1012<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 1013<p>Pointers and references to elements are never invalidated.</p> 1014</td> 1015</tr> 1016</tbody> 1017</table></div> 1018</li> 1019<li class="listitem"> 1020<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_42_8-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span> il<span class="special">)</span><span class="special">;</span></pre> 1021<p>Inserts a range of elements into the container. 1022 Elements are inserted if and only if there is no element in the container with an equivalent key. 1023 </p> 1024<div class="variablelist"><table border="0" class="variablelist compact"> 1025<colgroup> 1026<col align="left" valign="top"> 1027<col> 1028</colgroup> 1029<tbody> 1030<tr> 1031<td><p><span class="term">Requires:</span></p></td> 1032<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">EmplaceConstructible</code> into 1033 <code class="computeroutput">X</code> from <code class="computeroutput">*first</code>.</p></td> 1034</tr> 1035<tr> 1036<td><p><span class="term">Throws:</span></p></td> 1037<td><p>When inserting a single element, if an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 1038</tr> 1039<tr> 1040<td><p><span class="term">Notes:</span></p></td> 1041<td> 1042<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 1043<p>Pointers and references to elements are never invalidated.</p> 1044</td> 1045</tr> 1046</tbody> 1047</table></div> 1048</li> 1049<li class="listitem"> 1050<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_42_9-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">initializer_list</span><span class="special"><</span><span class="identifier">value_type</span><span class="special">></span> il<span class="special">)</span><span class="special">;</span></pre> 1051<p>Inserts a range of elements into the container. Elements are inserted if and only if there is no element in the container with an equivalent key.</p> 1052<div class="variablelist"><table border="0" class="variablelist compact"> 1053<colgroup> 1054<col align="left" valign="top"> 1055<col> 1056</colgroup> 1057<tbody> 1058<tr> 1059<td><p><span class="term">Requires:</span></p></td> 1060<td><p><code class="computeroutput">value_type</code> is <code class="computeroutput">EmplaceConstructible</code> into 1061 <code class="computeroutput">X</code> from <code class="computeroutput">*first</code>.</p></td> 1062</tr> 1063<tr> 1064<td><p><span class="term">Throws:</span></p></td> 1065<td><p>When inserting a single element, if an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 1066</tr> 1067<tr> 1068<td><p><span class="term">Notes:</span></p></td> 1069<td> 1070<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 1071<p>Pointers and references to elements are never invalidated.</p> 1072</td> 1073</tr> 1074</tbody> 1075</table></div> 1076</li> 1077<li class="listitem"> 1078<pre class="literallayout"><span class="identifier">node_type</span> <a name="id-1_3_45_10_2_1_1_42_10-bb"></a><span class="identifier">extract</span><span class="special">(</span><span class="identifier">const_iterator</span> position<span class="special">)</span><span class="special">;</span></pre> 1079<p>Removes the element pointed to by <code class="computeroutput">position</code>.</p> 1080<div class="variablelist"><table border="0" class="variablelist compact"> 1081<colgroup> 1082<col align="left" valign="top"> 1083<col> 1084</colgroup> 1085<tbody> 1086<tr> 1087<td><p><span class="term">Returns:</span></p></td> 1088<td><p>A <code class="computeroutput">node_type</code> owning the element.</p></td> 1089</tr> 1090<tr> 1091<td><p><span class="term">Notes:</span></p></td> 1092<td><p> 1093 In C++17 a node extracted using this method can be inserted into a compatible <code class="computeroutput">unordered_multimap</code>, 1094 but that is not supported yet. 1095 </p></td> 1096</tr> 1097</tbody> 1098</table></div> 1099</li> 1100<li class="listitem"> 1101<pre class="literallayout"><span class="identifier">node_type</span> <a name="id-1_3_45_10_2_1_1_42_11-bb"></a><span class="identifier">extract</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span><span class="special">;</span></pre> 1102<p>Removes an element with key equivalent to <code class="computeroutput">k</code>.</p> 1103<div class="variablelist"><table border="0" class="variablelist compact"> 1104<colgroup> 1105<col align="left" valign="top"> 1106<col> 1107</colgroup> 1108<tbody> 1109<tr> 1110<td><p><span class="term">Returns:</span></p></td> 1111<td><p>A <code class="computeroutput">node_type</code> owning the element if found, otherwise an empty <code class="computeroutput">node_type</code>.</p></td> 1112</tr> 1113<tr> 1114<td><p><span class="term">Throws:</span></p></td> 1115<td><p>Only throws an exception if it is thrown by <code class="computeroutput">hasher</code> or <code class="computeroutput">key_equal</code>.</p></td> 1116</tr> 1117<tr> 1118<td><p><span class="term">Notes:</span></p></td> 1119<td><p> 1120 In C++17 a node extracted using this method can be inserted into a compatible <code class="computeroutput">unordered_multimap</code>, 1121 but that is not supported yet. 1122 </p></td> 1123</tr> 1124</tbody> 1125</table></div> 1126</li> 1127<li class="listitem"> 1128<pre class="literallayout"><span class="identifier">insert_return_type</span> <a name="id-1_3_45_10_2_1_1_42_12-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">node_type</span><span class="special">&&</span> nh<span class="special">)</span><span class="special">;</span></pre> 1129<p>If <code class="computeroutput">nh</code> is empty, has no affect.</p> 1130<p>Otherwise inserts the element owned by <code class="computeroutput">nh</code> 1131 if and only if there is no element in the container with an equivalent key. 1132 </p> 1133<div class="variablelist"><table border="0" class="variablelist compact"> 1134<colgroup> 1135<col align="left" valign="top"> 1136<col> 1137</colgroup> 1138<tbody> 1139<tr> 1140<td><p><span class="term">Requires:</span></p></td> 1141<td><p><code class="computeroutput">nh</code> is empty or <code class="computeroutput">nh.get_allocator()</code> is equal to the container's allocator.</p></td> 1142</tr> 1143<tr> 1144<td><p><span class="term">Returns:</span></p></td> 1145<td> 1146<p>If <code class="computeroutput">nh</code> was empty, returns an <code class="computeroutput">insert_return_type</code> with: 1147 <code class="computeroutput">inserted</code> equal to <code class="computeroutput">false</code>, 1148 <code class="computeroutput">position</code> equal to <code class="computeroutput">end()</code> and 1149 <code class="computeroutput">node</code> empty.</p> 1150<p>Otherwise if there was already an element with an equivalent key, returns an <code class="computeroutput">insert_return_type</code> with: 1151 <code class="computeroutput">inserted</code> equal to <code class="computeroutput">false</code>, 1152 <code class="computeroutput">position</code> pointing to a matching element and 1153 <code class="computeroutput">node</code> contains the node from <code class="computeroutput">nh</code>.</p> 1154<p>Otherwise if the insertion succeeded, returns an <code class="computeroutput">insert_return_type</code> with: 1155 <code class="computeroutput">inserted</code> equal to <code class="computeroutput">true</code>, 1156 <code class="computeroutput">position</code> pointing to the newly inserted element and 1157 <code class="computeroutput">node</code> empty.</p> 1158</td> 1159</tr> 1160<tr> 1161<td><p><span class="term">Throws:</span></p></td> 1162<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 1163</tr> 1164<tr> 1165<td><p><span class="term">Notes:</span></p></td> 1166<td> 1167<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 1168<p>Pointers and references to elements are never invalidated.</p> 1169<p>In C++17 this can be used to insert a node extracted from a compatible <code class="computeroutput">unordered_multimap</code>, 1170 but that is not supported yet.</p> 1171</td> 1172</tr> 1173</tbody> 1174</table></div> 1175</li> 1176<li class="listitem"> 1177<pre class="literallayout"><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_42_13-bb"></a><span class="identifier">insert</span><span class="special">(</span><span class="identifier">const_iterator</span> hint<span class="special">,</span> <span class="identifier">node_type</span><span class="special">&&</span> nh<span class="special">)</span><span class="special">;</span></pre> 1178<p>If <code class="computeroutput">nh</code> is empty, has no affect.</p> 1179<p>Otherwise inserts the element owned by <code class="computeroutput">nh</code> 1180 if and only if there is no element in the container with an equivalent key. 1181 </p> 1182<p>If there is already an element in the container with an equivalent key has no effect on <code class="computeroutput">nh</code> (i.e. <code class="computeroutput">nh</code> still contains the node.)</p> 1183<p>hint is a suggestion to where the element should be inserted.</p> 1184<div class="variablelist"><table border="0" class="variablelist compact"> 1185<colgroup> 1186<col align="left" valign="top"> 1187<col> 1188</colgroup> 1189<tbody> 1190<tr> 1191<td><p><span class="term">Requires:</span></p></td> 1192<td><p><code class="computeroutput">nh</code> is empty or <code class="computeroutput">nh.get_allocator()</code> is equal to the container's allocator.</p></td> 1193</tr> 1194<tr> 1195<td><p><span class="term">Returns:</span></p></td> 1196<td> 1197<p>If <code class="computeroutput">nh</code> was empty returns <code class="computeroutput">end()</code>.</p> 1198<p>If there was already an element in the container with an equivalent key returns an iterator pointing to that.</p> 1199<p>Otherwise returns an iterator pointing to the newly inserted element.</p> 1200</td> 1201</tr> 1202<tr> 1203<td><p><span class="term">Throws:</span></p></td> 1204<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 1205</tr> 1206<tr> 1207<td><p><span class="term">Notes:</span></p></td> 1208<td> 1209<p>The standard is fairly vague on the meaning of the hint. But the only practical way to use it, and the only way that Boost.Unordered supports is to point to an existing element with the same key. </p> 1210<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 1211<p>Pointers and references to elements are never invalidated.</p> 1212<p>In C++17 this can be used to insert a node extracted from a compatible <code class="computeroutput">unordered_multimap</code>, 1213 but that is not supported yet.</p> 1214</td> 1215</tr> 1216</tbody> 1217</table></div> 1218</li> 1219<li class="listitem"> 1220<pre class="literallayout"><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_42_14-bb"></a><span class="identifier">erase</span><span class="special">(</span><span class="identifier">const_iterator</span> position<span class="special">)</span><span class="special">;</span></pre> 1221<p>Erase the element pointed to by <code class="computeroutput">position</code>.</p> 1222<div class="variablelist"><table border="0" class="variablelist compact"> 1223<colgroup> 1224<col align="left" valign="top"> 1225<col> 1226</colgroup> 1227<tbody> 1228<tr> 1229<td><p><span class="term">Returns:</span></p></td> 1230<td><p>The iterator following <code class="computeroutput">position</code> before the erasure.</p></td> 1231</tr> 1232<tr> 1233<td><p><span class="term">Throws:</span></p></td> 1234<td><p>Only throws an exception if it is thrown by <code class="computeroutput">hasher</code> or <code class="computeroutput">key_equal</code>.</p></td> 1235</tr> 1236<tr> 1237<td><p><span class="term">Notes:</span></p></td> 1238<td><p> 1239 In older versions this could be inefficient because it had to search 1240 through several buckets to find the position of the returned iterator. 1241 The data structure has been changed so that this is no longer the case, 1242 and the alternative erase methods have been deprecated. 1243 </p></td> 1244</tr> 1245</tbody> 1246</table></div> 1247</li> 1248<li class="listitem"> 1249<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_42_15-bb"></a><span class="identifier">erase</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span><span class="special">;</span></pre> 1250<p>Erase all elements with key equivalent to <code class="computeroutput">k</code>.</p> 1251<div class="variablelist"><table border="0" class="variablelist compact"> 1252<colgroup> 1253<col align="left" valign="top"> 1254<col> 1255</colgroup> 1256<tbody> 1257<tr> 1258<td><p><span class="term">Returns:</span></p></td> 1259<td><p>The number of elements erased.</p></td> 1260</tr> 1261<tr> 1262<td><p><span class="term">Throws:</span></p></td> 1263<td><p>Only throws an exception if it is thrown by <code class="computeroutput">hasher</code> or <code class="computeroutput">key_equal</code>.</p></td> 1264</tr> 1265</tbody> 1266</table></div> 1267</li> 1268<li class="listitem"> 1269<pre class="literallayout"><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_42_16-bb"></a><span class="identifier">erase</span><span class="special">(</span><span class="identifier">const_iterator</span> first<span class="special">,</span> <span class="identifier">const_iterator</span> last<span class="special">)</span><span class="special">;</span></pre> 1270<p>Erases the elements in the range from <code class="computeroutput">first</code> to <code class="computeroutput">last</code>.</p> 1271<div class="variablelist"><table border="0" class="variablelist compact"> 1272<colgroup> 1273<col align="left" valign="top"> 1274<col> 1275</colgroup> 1276<tbody> 1277<tr> 1278<td><p><span class="term">Returns:</span></p></td> 1279<td><p>The iterator following the erased elements - i.e. <code class="computeroutput">last</code>.</p></td> 1280</tr> 1281<tr> 1282<td><p><span class="term">Throws:</span></p></td> 1283<td> 1284<p>Only throws an exception if it is thrown by <code class="computeroutput">hasher</code> or <code class="computeroutput">key_equal</code>.</p> 1285<p>In this implementation, this overload doesn't call either function object's methods so it is no throw, but this might not be true in other implementations.</p> 1286</td> 1287</tr> 1288</tbody> 1289</table></div> 1290</li> 1291<li class="listitem"> 1292<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_42_17-bb"></a><span class="identifier">quick_erase</span><span class="special">(</span><span class="identifier">const_iterator</span> position<span class="special">)</span><span class="special">;</span></pre> 1293<p>Erase the element pointed to by <code class="computeroutput">position</code>.</p> 1294<div class="variablelist"><table border="0" class="variablelist compact"> 1295<colgroup> 1296<col align="left" valign="top"> 1297<col> 1298</colgroup> 1299<tbody> 1300<tr> 1301<td><p><span class="term">Throws:</span></p></td> 1302<td> 1303<p>Only throws an exception if it is thrown by <code class="computeroutput">hasher</code> or <code class="computeroutput">key_equal</code>.</p> 1304<p>In this implementation, this overload doesn't call either function object's methods so it is no throw, but this might not be true in other implementations.</p> 1305</td> 1306</tr> 1307<tr> 1308<td><p><span class="term">Notes:</span></p></td> 1309<td><p> 1310 This method was implemented because returning an iterator to 1311 the next element from <code class="computeroutput">erase</code> was expensive, but 1312 the container has been redesigned so that is no longer the 1313 case. So this method is now deprecated. 1314 </p></td> 1315</tr> 1316</tbody> 1317</table></div> 1318</li> 1319<li class="listitem"> 1320<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_42_18-bb"></a><span class="identifier">erase_return_void</span><span class="special">(</span><span class="identifier">const_iterator</span> position<span class="special">)</span><span class="special">;</span></pre> 1321<p>Erase the element pointed to by <code class="computeroutput">position</code>.</p> 1322<div class="variablelist"><table border="0" class="variablelist compact"> 1323<colgroup> 1324<col align="left" valign="top"> 1325<col> 1326</colgroup> 1327<tbody> 1328<tr> 1329<td><p><span class="term">Throws:</span></p></td> 1330<td> 1331<p>Only throws an exception if it is thrown by <code class="computeroutput">hasher</code> or <code class="computeroutput">key_equal</code>.</p> 1332<p>In this implementation, this overload doesn't call either function object's methods so it is no throw, but this might not be true in other implementations.</p> 1333</td> 1334</tr> 1335<tr> 1336<td><p><span class="term">Notes:</span></p></td> 1337<td><p> 1338 This method was implemented because returning an iterator to 1339 the next element from <code class="computeroutput">erase</code> was expensive, but 1340 the container has been redesigned so that is no longer the 1341 case. So this method is now deprecated. 1342 </p></td> 1343</tr> 1344</tbody> 1345</table></div> 1346</li> 1347<li class="listitem"> 1348<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_42_19-bb"></a><span class="identifier">clear</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 1349<p>Erases all elements in the container.</p> 1350<div class="variablelist"><table border="0" class="variablelist compact"> 1351<colgroup> 1352<col align="left" valign="top"> 1353<col> 1354</colgroup> 1355<tbody> 1356<tr> 1357<td><p><span class="term">Postconditions:</span></p></td> 1358<td><p><code class="computeroutput"><a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_40_2-bb">size</a>() == 0</code></p></td> 1359</tr> 1360<tr> 1361<td><p><span class="term">Throws:</span></p></td> 1362<td><p>Never throws an exception.</p></td> 1363</tr> 1364</tbody> 1365</table></div> 1366</li> 1367<li class="listitem"> 1368<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_42_20-bb"></a><span class="identifier">swap</span><span class="special">(</span><span class="identifier">unordered_map</span><span class="special">&</span><span class="special">)</span><span class="special">;</span></pre> 1369<p>Swaps the contents of the container with the parameter.</p> 1370<p>If <code class="computeroutput">Allocator::propagate_on_container_swap</code> is declared and 1371 <code class="computeroutput">Allocator::propagate_on_container_swap::value</code> is true then the 1372 containers' allocators are swapped. Otherwise, swapping with unequal allocators 1373 results in undefined behavior.</p> 1374<div class="variablelist"><table border="0" class="variablelist compact"> 1375<colgroup> 1376<col align="left" valign="top"> 1377<col> 1378</colgroup> 1379<tbody> 1380<tr> 1381<td><p><span class="term">Throws:</span></p></td> 1382<td><p>Doesn't throw an exception unless it is thrown by the copy constructor or copy assignment operator of <code class="computeroutput">key_equal</code> or <code class="computeroutput">hasher</code>.</p></td> 1383</tr> 1384<tr> 1385<td><p><span class="term">Notes:</span></p></td> 1386<td><p>The exception specifications aren't quite the same as the C++11 standard, as 1387 the equality predieate and hash function are swapped using their copy constructors.</p></td> 1388</tr> 1389</tbody> 1390</table></div> 1391</li> 1392<li class="listitem"> 1393<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> H2<span class="special">,</span> <span class="keyword">typename</span> P2<span class="special">></span> 1394 <a name="id-1_3_45_10_2_1_1_42_21-bb"></a><span class="identifier">merge</span><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">H2</span><span class="special">,</span> <span class="identifier">P2</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&</span> source<span class="special">)</span><span class="special">;</span></pre> 1395<div class="variablelist"><table border="0" class="variablelist compact"> 1396<colgroup> 1397<col align="left" valign="top"> 1398<col> 1399</colgroup> 1400<tbody><tr> 1401<td><p><span class="term">Notes:</span></p></td> 1402<td><p>Does not support merging with a compatible <code class="computeroutput">unordered_multimap</code> yet.</p></td> 1403</tr></tbody> 1404</table></div> 1405</li> 1406<li class="listitem"> 1407<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> H2<span class="special">,</span> <span class="keyword">typename</span> P2<span class="special">></span> 1408 <a name="id-1_3_45_10_2_1_1_42_22-bb"></a><span class="identifier">merge</span><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">H2</span><span class="special">,</span> <span class="identifier">P2</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&&</span> source<span class="special">)</span><span class="special">;</span></pre> 1409<div class="variablelist"><table border="0" class="variablelist compact"> 1410<colgroup> 1411<col align="left" valign="top"> 1412<col> 1413</colgroup> 1414<tbody><tr> 1415<td><p><span class="term">Notes:</span></p></td> 1416<td><p>Does not support merging with a compatible <code class="computeroutput">unordered_multimap</code> yet.</p></td> 1417</tr></tbody> 1418</table></div> 1419</li> 1420</ol></div> 1421</div> 1422<div class="refsect2"> 1423<a name="id-1.3.45.10.3.4.4.22"></a><h3> 1424<a name="id-1_3_45_10_2_1_1_43-bb"></a><code class="computeroutput">unordered_map</code> observers</h3> 1425<div class="orderedlist"><ol class="orderedlist" type="1"> 1426<li class="listitem"> 1427<pre class="literallayout"><span class="identifier">hasher</span> <a name="id-1_3_45_10_2_1_1_43_1-bb"></a><span class="identifier">hash_function</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1428<div class="variablelist"><table border="0" class="variablelist compact"> 1429<colgroup> 1430<col align="left" valign="top"> 1431<col> 1432</colgroup> 1433<tbody><tr> 1434<td><p><span class="term">Returns:</span></p></td> 1435<td>The container's hash function. 1436 </td> 1437</tr></tbody> 1438</table></div> 1439</li> 1440<li class="listitem"> 1441<pre class="literallayout"><span class="identifier">key_equal</span> <a name="id-1_3_45_10_2_1_1_43_2-bb"></a><span class="identifier">key_eq</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1442<div class="variablelist"><table border="0" class="variablelist compact"> 1443<colgroup> 1444<col align="left" valign="top"> 1445<col> 1446</colgroup> 1447<tbody><tr> 1448<td><p><span class="term">Returns:</span></p></td> 1449<td>The container's key equality predicate. 1450 </td> 1451</tr></tbody> 1452</table></div> 1453</li> 1454</ol></div> 1455</div> 1456<div class="refsect2"> 1457<a name="id-1.3.45.10.3.4.4.23"></a><h3> 1458<a name="id-1_3_45_10_2_1_1_44-bb"></a><code class="computeroutput">unordered_map</code> lookup</h3> 1459<div class="orderedlist"><ol class="orderedlist" type="1"> 1460<li class="listitem"> 1461<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_44_1-bb"></a><span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_44_1_1-bb"></a><span class="identifier">find</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span><span class="special">;</span> 1462<span class="identifier">const_iterator</span> <a name="id-1_3_45_10_2_1_1_44_1_2-bb"></a><span class="identifier">find</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 1463<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> CompatibleKey<span class="special">,</span> <span class="keyword">typename</span> CompatibleHash<span class="special">,</span> 1464 <span class="keyword">typename</span> CompatiblePredicate<span class="special">></span> 1465 <span class="identifier">iterator</span> <a name="id-1_3_45_10_2_1_1_44_1_3-bb"></a><span class="identifier">find</span><span class="special">(</span><span class="identifier">CompatibleKey</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">,</span> <span class="identifier">CompatibleHash</span> <span class="keyword">const</span><span class="special">&</span> hash<span class="special">,</span> 1466 <span class="identifier">CompatiblePredicate</span> <span class="keyword">const</span><span class="special">&</span> eq<span class="special">)</span><span class="special">;</span> 1467<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> CompatibleKey<span class="special">,</span> <span class="keyword">typename</span> CompatibleHash<span class="special">,</span> 1468 <span class="keyword">typename</span> CompatiblePredicate<span class="special">></span> 1469 <span class="identifier">const_iterator</span> 1470 <a name="id-1_3_45_10_2_1_1_44_1_4-bb"></a><span class="identifier">find</span><span class="special">(</span><span class="identifier">CompatibleKey</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">,</span> <span class="identifier">CompatibleHash</span> <span class="keyword">const</span><span class="special">&</span> hash<span class="special">,</span> 1471 <span class="identifier">CompatiblePredicate</span> <span class="keyword">const</span><span class="special">&</span> eq<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1472<div class="variablelist"><table border="0" class="variablelist compact"> 1473<colgroup> 1474<col align="left" valign="top"> 1475<col> 1476</colgroup> 1477<tbody> 1478<tr> 1479<td><p><span class="term">Returns:</span></p></td> 1480<td><p>An iterator pointing to an element with key equivalent to <code class="computeroutput">k</code>, or <code class="computeroutput">b.end()</code> if no such element exists.</p></td> 1481</tr> 1482<tr> 1483<td><p><span class="term">Notes:</span></p></td> 1484<td><p> 1485 The templated overloads are a non-standard extensions which 1486 allows you to use a compatible hash function and equality 1487 predicate for a key of a different type in order to avoid 1488 an expensive type cast. In general, its use is not encouraged. 1489 </p></td> 1490</tr> 1491</tbody> 1492</table></div> 1493</li> 1494<li class="listitem"> 1495<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_44_2-bb"></a><span class="identifier">count</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1496<div class="variablelist"><table border="0" class="variablelist compact"> 1497<colgroup> 1498<col align="left" valign="top"> 1499<col> 1500</colgroup> 1501<tbody><tr> 1502<td><p><span class="term">Returns:</span></p></td> 1503<td><p>The number of elements with key equivalent to <code class="computeroutput">k</code>.</p></td> 1504</tr></tbody> 1505</table></div> 1506</li> 1507<li class="listitem"> 1508<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_44_3-bb"></a><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> <a name="id-1_3_45_10_2_1_1_44_3_1-bb"></a><span class="identifier">equal_range</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span><span class="special">;</span> 1509<span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span><span class="special"><</span><span class="identifier">const_iterator</span><span class="special">,</span> <span class="identifier">const_iterator</span><span class="special">></span> <a name="id-1_3_45_10_2_1_1_44_3_2-bb"></a><span class="identifier">equal_range</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1510<div class="variablelist"><table border="0" class="variablelist compact"> 1511<colgroup> 1512<col align="left" valign="top"> 1513<col> 1514</colgroup> 1515<tbody><tr> 1516<td><p><span class="term">Returns:</span></p></td> 1517<td><p>A range containing all elements with key equivalent to <code class="computeroutput">k</code>. 1518 If the container doesn't container any such elements, returns 1519 <code class="computeroutput">std::make_pair(b.end(),b.end())</code>. 1520 </p></td> 1521</tr></tbody> 1522</table></div> 1523</li> 1524<li class="listitem"> 1525<pre class="literallayout"><span class="identifier">mapped_type</span><span class="special">&</span> <a name="id-1_3_45_10_2_1_1_44_4-bb"></a><span class="keyword">operator</span><span class="special">[</span><span class="special">]</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span><span class="special">;</span></pre> 1526<div class="variablelist"><table border="0" class="variablelist compact"> 1527<colgroup> 1528<col align="left" valign="top"> 1529<col> 1530</colgroup> 1531<tbody> 1532<tr> 1533<td><p><span class="term">Effects:</span></p></td> 1534<td><p>If the container does not already contain an elements with a key equivalent to <code class="computeroutput">k</code>, inserts the value <code class="computeroutput">std::pair<key_type const, mapped_type>(k, mapped_type())</code></p></td> 1535</tr> 1536<tr> 1537<td><p><span class="term">Returns:</span></p></td> 1538<td><p>A reference to <code class="computeroutput">x.second</code> where x is the element already in the container, or the newly inserted element with a key equivalent to <code class="computeroutput">k</code></p></td> 1539</tr> 1540<tr> 1541<td><p><span class="term">Throws:</span></p></td> 1542<td><p>If an exception is thrown by an operation other than a call to <code class="computeroutput">hasher</code> the function has no effect.</p></td> 1543</tr> 1544<tr> 1545<td><p><span class="term">Notes:</span></p></td> 1546<td> 1547<p>Can invalidate iterators, but only if the insert causes the load factor to be greater to or equal to the maximum load factor.</p> 1548<p>Pointers and references to elements are never invalidated.</p> 1549</td> 1550</tr> 1551</tbody> 1552</table></div> 1553</li> 1554<li class="listitem"> 1555<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_44_5-bb"></a><span class="identifier">Mapped</span><span class="special">&</span> <a name="id-1_3_45_10_2_1_1_44_5_1-bb"></a><span class="identifier">at</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span><span class="special">;</span> 1556<span class="identifier">Mapped</span> <span class="keyword">const</span><span class="special">&</span> <a name="id-1_3_45_10_2_1_1_44_5_2-bb"></a><span class="identifier">at</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1557<div class="variablelist"><table border="0" class="variablelist compact"> 1558<colgroup> 1559<col align="left" valign="top"> 1560<col> 1561</colgroup> 1562<tbody> 1563<tr> 1564<td><p><span class="term">Returns:</span></p></td> 1565<td><p>A reference to <code class="computeroutput">x.second</code> where <code class="computeroutput">x</code> is the (unique) element whose key is equivalent to <code class="computeroutput">k</code>.</p></td> 1566</tr> 1567<tr> 1568<td><p><span class="term">Throws:</span></p></td> 1569<td><p>An exception object of type <code class="computeroutput">std::out_of_range</code> if no such element is present.</p></td> 1570</tr> 1571</tbody> 1572</table></div> 1573</li> 1574</ol></div> 1575</div> 1576<div class="refsect2"> 1577<a name="id-1.3.45.10.3.4.4.24"></a><h3> 1578<a name="id-1_3_45_10_2_1_1_45-bb"></a><code class="computeroutput">unordered_map</code> bucket interface</h3> 1579<div class="orderedlist"><ol class="orderedlist" type="1"> 1580<li class="listitem"> 1581<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_45_1-bb"></a><span class="identifier">bucket_count</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1582<div class="variablelist"><table border="0" class="variablelist compact"> 1583<colgroup> 1584<col align="left" valign="top"> 1585<col> 1586</colgroup> 1587<tbody><tr> 1588<td><p><span class="term">Returns:</span></p></td> 1589<td><p>The number of buckets.</p></td> 1590</tr></tbody> 1591</table></div> 1592</li> 1593<li class="listitem"> 1594<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_45_2-bb"></a><span class="identifier">max_bucket_count</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1595<div class="variablelist"><table border="0" class="variablelist compact"> 1596<colgroup> 1597<col align="left" valign="top"> 1598<col> 1599</colgroup> 1600<tbody><tr> 1601<td><p><span class="term">Returns:</span></p></td> 1602<td><p>An upper bound on the number of buckets.</p></td> 1603</tr></tbody> 1604</table></div> 1605</li> 1606<li class="listitem"> 1607<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_45_3-bb"></a><span class="identifier">bucket_size</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1608<div class="variablelist"><table border="0" class="variablelist compact"> 1609<colgroup> 1610<col align="left" valign="top"> 1611<col> 1612</colgroup> 1613<tbody> 1614<tr> 1615<td><p><span class="term">Requires:</span></p></td> 1616<td><p><code class="computeroutput">n < <a class="link" href="unordered_map.html#id-1_3_45_10_2_1_1_45_1-bb">bucket_count</a>()</code></p></td> 1617</tr> 1618<tr> 1619<td><p><span class="term">Returns:</span></p></td> 1620<td><p>The number of elements in bucket <code class="computeroutput">n</code>.</p></td> 1621</tr> 1622</tbody> 1623</table></div> 1624</li> 1625<li class="listitem"> 1626<pre class="literallayout"><span class="identifier">size_type</span> <a name="id-1_3_45_10_2_1_1_45_4-bb"></a><span class="identifier">bucket</span><span class="special">(</span><span class="identifier">key_type</span> <span class="keyword">const</span><span class="special">&</span> k<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1627<div class="variablelist"><table border="0" class="variablelist compact"> 1628<colgroup> 1629<col align="left" valign="top"> 1630<col> 1631</colgroup> 1632<tbody> 1633<tr> 1634<td><p><span class="term">Returns:</span></p></td> 1635<td><p>The index of the bucket which would contain an element with key <code class="computeroutput">k</code>.</p></td> 1636</tr> 1637<tr> 1638<td><p><span class="term">Postconditions:</span></p></td> 1639<td><p>The return value is less than <code class="computeroutput">bucket_count()</code></p></td> 1640</tr> 1641</tbody> 1642</table></div> 1643</li> 1644<li class="listitem"> 1645<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_45_5-bb"></a><span class="identifier">local_iterator</span> <a name="id-1_3_45_10_2_1_1_45_5_1-bb"></a><span class="identifier">begin</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span><span class="special">;</span> 1646<span class="identifier">const_local_iterator</span> <a name="id-1_3_45_10_2_1_1_45_5_2-bb"></a><span class="identifier">begin</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1647<div class="variablelist"><table border="0" class="variablelist compact"> 1648<colgroup> 1649<col align="left" valign="top"> 1650<col> 1651</colgroup> 1652<tbody> 1653<tr> 1654<td><p><span class="term">Requires:</span></p></td> 1655<td><p><code class="computeroutput">n</code> shall be in the range <code class="computeroutput">[0, bucket_count())</code>.</p></td> 1656</tr> 1657<tr> 1658<td><p><span class="term">Returns:</span></p></td> 1659<td><p>A local iterator pointing the first element in the bucket with index <code class="computeroutput">n</code>.</p></td> 1660</tr> 1661</tbody> 1662</table></div> 1663</li> 1664<li class="listitem"> 1665<pre class="literallayout"><a name="id-1_3_45_10_2_1_1_45_6-bb"></a><span class="identifier">local_iterator</span> <a name="id-1_3_45_10_2_1_1_45_6_1-bb"></a><span class="identifier">end</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span><span class="special">;</span> 1666<span class="identifier">const_local_iterator</span> <a name="id-1_3_45_10_2_1_1_45_6_2-bb"></a><span class="identifier">end</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1667<div class="variablelist"><table border="0" class="variablelist compact"> 1668<colgroup> 1669<col align="left" valign="top"> 1670<col> 1671</colgroup> 1672<tbody> 1673<tr> 1674<td><p><span class="term">Requires:</span></p></td> 1675<td><p><code class="computeroutput">n</code> shall be in the range <code class="computeroutput">[0, bucket_count())</code>.</p></td> 1676</tr> 1677<tr> 1678<td><p><span class="term">Returns:</span></p></td> 1679<td><p>A local iterator pointing the 'one past the end' element in the bucket with index <code class="computeroutput">n</code>.</p></td> 1680</tr> 1681</tbody> 1682</table></div> 1683</li> 1684<li class="listitem"> 1685<pre class="literallayout"><span class="identifier">const_local_iterator</span> <a name="id-1_3_45_10_2_1_1_45_7-bb"></a><span class="identifier">cbegin</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1686<div class="variablelist"><table border="0" class="variablelist compact"> 1687<colgroup> 1688<col align="left" valign="top"> 1689<col> 1690</colgroup> 1691<tbody> 1692<tr> 1693<td><p><span class="term">Requires:</span></p></td> 1694<td><p><code class="computeroutput">n</code> shall be in the range <code class="computeroutput">[0, bucket_count())</code>.</p></td> 1695</tr> 1696<tr> 1697<td><p><span class="term">Returns:</span></p></td> 1698<td><p>A constant local iterator pointing the first element in the bucket with index <code class="computeroutput">n</code>.</p></td> 1699</tr> 1700</tbody> 1701</table></div> 1702</li> 1703<li class="listitem"> 1704<pre class="literallayout"><span class="identifier">const_local_iterator</span> <a name="id-1_3_45_10_2_1_1_45_8-bb"></a><span class="identifier">cend</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span><span class="special">;</span></pre> 1705<div class="variablelist"><table border="0" class="variablelist compact"> 1706<colgroup> 1707<col align="left" valign="top"> 1708<col> 1709</colgroup> 1710<tbody> 1711<tr> 1712<td><p><span class="term">Requires:</span></p></td> 1713<td><p><code class="computeroutput">n</code> shall be in the range <code class="computeroutput">[0, bucket_count())</code>.</p></td> 1714</tr> 1715<tr> 1716<td><p><span class="term">Returns:</span></p></td> 1717<td><p>A constant local iterator pointing the 'one past the end' element in the bucket with index <code class="computeroutput">n</code>.</p></td> 1718</tr> 1719</tbody> 1720</table></div> 1721</li> 1722</ol></div> 1723</div> 1724<div class="refsect2"> 1725<a name="id-1.3.45.10.3.4.4.25"></a><h3> 1726<a name="id-1_3_45_10_2_1_1_46-bb"></a><code class="computeroutput">unordered_map</code> hash policy</h3> 1727<div class="orderedlist"><ol class="orderedlist" type="1"> 1728<li class="listitem"> 1729<pre class="literallayout"><span class="keyword">float</span> <a name="id-1_3_45_10_2_1_1_46_1-bb"></a><span class="identifier">load_factor</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1730<div class="variablelist"><table border="0" class="variablelist compact"> 1731<colgroup> 1732<col align="left" valign="top"> 1733<col> 1734</colgroup> 1735<tbody><tr> 1736<td><p><span class="term">Returns:</span></p></td> 1737<td><p>The average number of elements per bucket.</p></td> 1738</tr></tbody> 1739</table></div> 1740</li> 1741<li class="listitem"> 1742<pre class="literallayout"><span class="keyword">float</span> <a name="id-1_3_45_10_2_1_1_46_2-bb"></a><span class="identifier">max_load_factor</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 1743<div class="variablelist"><table border="0" class="variablelist compact"> 1744<colgroup> 1745<col align="left" valign="top"> 1746<col> 1747</colgroup> 1748<tbody><tr> 1749<td><p><span class="term">Returns:</span></p></td> 1750<td><p>Returns the current maximum load factor.</p></td> 1751</tr></tbody> 1752</table></div> 1753</li> 1754<li class="listitem"> 1755<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_46_3-bb"></a><span class="identifier">max_load_factor</span><span class="special">(</span><span class="keyword">float</span> z<span class="special">)</span><span class="special">;</span></pre> 1756<div class="variablelist"><table border="0" class="variablelist compact"> 1757<colgroup> 1758<col align="left" valign="top"> 1759<col> 1760</colgroup> 1761<tbody><tr> 1762<td><p><span class="term">Effects:</span></p></td> 1763<td><p>Changes the container's maximum load factor, using <code class="computeroutput">z</code> as a hint.</p></td> 1764</tr></tbody> 1765</table></div> 1766</li> 1767<li class="listitem"> 1768<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_46_4-bb"></a><span class="identifier">rehash</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span><span class="special">;</span></pre> 1769<p>Changes the number of buckets so that there at least <code class="computeroutput">n</code> buckets, and so that the load factor is less than the maximum load factor.</p> 1770<p>Invalidates iterators, and changes the order of elements. Pointers and references to elements are not invalidated.</p> 1771<div class="variablelist"><table border="0" class="variablelist compact"> 1772<colgroup> 1773<col align="left" valign="top"> 1774<col> 1775</colgroup> 1776<tbody><tr> 1777<td><p><span class="term">Throws:</span></p></td> 1778<td><p>The function has no effect if an exception is thrown, unless it is thrown by the container's hash function or comparison function.</p></td> 1779</tr></tbody> 1780</table></div> 1781</li> 1782<li class="listitem"> 1783<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_45_10_2_1_1_46_5-bb"></a><span class="identifier">reserve</span><span class="special">(</span><span class="identifier">size_type</span> n<span class="special">)</span><span class="special">;</span></pre> 1784<p>Invalidates iterators, and changes the order of elements. Pointers and references to elements are not invalidated.</p> 1785<div class="variablelist"><table border="0" class="variablelist compact"> 1786<colgroup> 1787<col align="left" valign="top"> 1788<col> 1789</colgroup> 1790<tbody><tr> 1791<td><p><span class="term">Throws:</span></p></td> 1792<td><p>The function has no effect if an exception is thrown, unless it is thrown by the container's hash function or comparison function.</p></td> 1793</tr></tbody> 1794</table></div> 1795</li> 1796</ol></div> 1797</div> 1798<div class="refsect2"> 1799<a name="id-1.3.45.10.3.4.4.26"></a><h3> 1800<a name="id-1_3_45_10_2_1_1_47-bb"></a><code class="computeroutput">unordered_map</code> Equality Comparisons</h3> 1801<div class="orderedlist"><ol class="orderedlist" type="1"> 1802<li class="listitem"> 1803<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Mapped<span class="special">,</span> <span class="keyword">typename</span> Hash<span class="special">,</span> <span class="keyword">typename</span> Pred<span class="special">,</span> 1804 <span class="keyword">typename</span> Alloc<span class="special">></span> 1805 <span class="keyword">bool</span> <a name="boost.unordered_map.operator=="></a><span class="keyword">operator</span><span class="special">==</span><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span> x<span class="special">,</span> 1806 <span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span> y<span class="special">)</span><span class="special">;</span></pre> 1807<p>Return <code class="computeroutput">true</code> if <code class="computeroutput">x.size() == 1808 y.size</code> and for every element in <code class="computeroutput">x</code>, 1809 there is an element in <code class="computeroutput">y</code> with the same 1810 for the same key, with an equal value (using 1811 <code class="computeroutput">operator==</code> to compare the value types). 1812 </p> 1813<div class="variablelist"><table border="0" class="variablelist compact"> 1814<colgroup> 1815<col align="left" valign="top"> 1816<col> 1817</colgroup> 1818<tbody><tr> 1819<td><p><span class="term">Notes:</span></p></td> 1820<td> 1821<p>The behavior of this function was changed to match 1822 the C++11 standard in Boost 1.48.</p> 1823<p>Behavior is undefined if the two containers don't have 1824 equivalent equality predicates.</p> 1825</td> 1826</tr></tbody> 1827</table></div> 1828</li> 1829<li class="listitem"> 1830<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Mapped<span class="special">,</span> <span class="keyword">typename</span> Hash<span class="special">,</span> <span class="keyword">typename</span> Pred<span class="special">,</span> 1831 <span class="keyword">typename</span> Alloc<span class="special">></span> 1832 <span class="keyword">bool</span> <a name="boost.unordered_map.operator!="></a><span class="keyword">operator</span><span class="special">!=</span><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span> x<span class="special">,</span> 1833 <span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span> y<span class="special">)</span><span class="special">;</span></pre> 1834<p>Return <code class="computeroutput">false</code> if <code class="computeroutput">x.size() == 1835 y.size</code> and for every element in <code class="computeroutput">x</code>, 1836 there is an element in <code class="computeroutput">y</code> with the same 1837 for the same key, with an equal value (using 1838 <code class="computeroutput">operator==</code> to compare the value types). 1839 </p> 1840<div class="variablelist"><table border="0" class="variablelist compact"> 1841<colgroup> 1842<col align="left" valign="top"> 1843<col> 1844</colgroup> 1845<tbody><tr> 1846<td><p><span class="term">Notes:</span></p></td> 1847<td> 1848<p>The behavior of this function was changed to match 1849 the C++11 standard in Boost 1.48.</p> 1850<p>Behavior is undefined if the two containers don't have 1851 equivalent equality predicates.</p> 1852</td> 1853</tr></tbody> 1854</table></div> 1855</li> 1856</ol></div> 1857</div> 1858<div class="refsect2"> 1859<a name="id-1.3.45.10.3.4.4.27"></a><h3> 1860<a name="id-1_3_45_10_2_1_1_48-bb"></a><code class="computeroutput">unordered_map</code> swap</h3> 1861<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 1862<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Key<span class="special">,</span> <span class="keyword">typename</span> Mapped<span class="special">,</span> <span class="keyword">typename</span> Hash<span class="special">,</span> <span class="keyword">typename</span> Pred<span class="special">,</span> 1863 <span class="keyword">typename</span> Alloc<span class="special">></span> 1864 <span class="keyword">void</span> <a name="boost.unordered_map.swap"></a><span class="identifier">swap</span><span class="special">(</span><span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&</span> x<span class="special">,</span> 1865 <span class="identifier">unordered_map</span><span class="special"><</span><span class="identifier">Key</span><span class="special">,</span> <span class="identifier">Mapped</span><span class="special">,</span> <span class="identifier">Hash</span><span class="special">,</span> <span class="identifier">Pred</span><span class="special">,</span> <span class="identifier">Alloc</span><span class="special">></span><span class="special">&</span> y<span class="special">)</span><span class="special">;</span></pre> 1866<p>Swaps the contents of <code class="computeroutput">x</code> and <code class="computeroutput">y</code>.</p> 1867<p>If <code class="computeroutput">Allocator::propagate_on_container_swap</code> is declared and 1868 <code class="computeroutput">Allocator::propagate_on_container_swap::value</code> is true then the 1869 containers' allocators are swapped. Otherwise, swapping with unequal allocators 1870 results in undefined behavior.</p> 1871<div class="variablelist"><table border="0" class="variablelist compact"> 1872<colgroup> 1873<col align="left" valign="top"> 1874<col> 1875</colgroup> 1876<tbody> 1877<tr> 1878<td><p><span class="term">Effects:</span></p></td> 1879<td><p><code class="computeroutput">x.swap(y)</code></p></td> 1880</tr> 1881<tr> 1882<td><p><span class="term">Throws:</span></p></td> 1883<td><p>Doesn't throw an exception unless it is thrown by the copy constructor or copy assignment operator of <code class="computeroutput">key_equal</code> or <code class="computeroutput">hasher</code>.</p></td> 1884</tr> 1885<tr> 1886<td><p><span class="term">Notes:</span></p></td> 1887<td><p>The exception specifications aren't quite the same as the C++11 standard, as 1888 the equality predieate and hash function are swapped using their copy constructors.</p></td> 1889</tr> 1890</tbody> 1891</table></div> 1892</li></ol></div> 1893</div> 1894</div> 1895</div> 1896<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 1897<td align="left"></td> 1898<td align="right"><div class="copyright-footer">Copyright © 2003, 2004 Jeremy B. Maitin-Shepard<br>Copyright © 2005-2008 Daniel 1899 James<p> 1900 Distributed under the Boost Software License, Version 1.0. (See accompanying 1901 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 1902 </p> 1903</div></td> 1904</tr></table> 1905<hr> 1906<div class="spirit-nav"> 1907<a accesskey="p" href="unordered/node_handle_map.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../unordered/reference.html#header.boost.unordered_map_hpp"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="unordered_multimap.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> 1908</div> 1909</body> 1910</html> 1911
