1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Random Access Range</title> 5<link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../index.html" title="Chapter 1. Range 2.0"> 8<link rel="up" href="../concepts.html" title="Range Concepts"> 9<link rel="prev" href="bidirectional_range.html" title="Bidirectional Range"> 10<link rel="next" href="concept_checking.html" title="Concept Checking"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="bidirectional_range.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><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="concept_checking.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="range.concepts.random_access_range"></a><a class="link" href="random_access_range.html" title="Random Access Range">Random Access Range</a> 28</h3></div></div></div> 29<h5> 30<a name="range.concepts.random_access_range.h0"></a> 31 <span class="phrase"><a name="range.concepts.random_access_range.description"></a></span><a class="link" href="random_access_range.html#range.concepts.random_access_range.description">Description</a> 32 </h5> 33<p> 34 A range <code class="computeroutput"><span class="identifier">X</span></code> where <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_iterator</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> is a model of <a href="../../../../../../libs/iterator/doc/new-iter-concepts.html#random-access-traversal-iterators-lib-random-access-traversal-iterators" target="_top">Random 35 Access Traversal Iterator</a>. 36 </p> 37<h5> 38<a name="range.concepts.random_access_range.h1"></a> 39 <span class="phrase"><a name="range.concepts.random_access_range.refinement_of"></a></span><a class="link" href="random_access_range.html#range.concepts.random_access_range.refinement_of">Refinement 40 of</a> 41 </h5> 42<p> 43 <a class="link" href="bidirectional_range.html" title="Bidirectional Range">Bidirectional Range</a> 44 </p> 45<h5> 46<a name="range.concepts.random_access_range.h2"></a> 47 <span class="phrase"><a name="range.concepts.random_access_range.valid_expressions"></a></span><a class="link" href="random_access_range.html#range.concepts.random_access_range.valid_expressions">Valid expressions</a> 48 </h5> 49<div class="informaltable"><table class="table"> 50<colgroup> 51<col> 52<col> 53<col> 54</colgroup> 55<thead><tr> 56<th> 57 <p> 58 Name 59 </p> 60 </th> 61<th> 62 <p> 63 Expression 64 </p> 65 </th> 66<th> 67 <p> 68 Return type 69 </p> 70 </th> 71</tr></thead> 72<tbody><tr> 73<td> 74 <p> 75 Size of range 76 </p> 77 </td> 78<td> 79 <p> 80 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">size</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span></code> 81 </p> 82 </td> 83<td> 84 <p> 85 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_size</span><span class="special"><</span><span class="identifier">X</span><span class="special">>::</span><span class="identifier">type</span></code> 86 </p> 87 </td> 88</tr></tbody> 89</table></div> 90<h5> 91<a name="range.concepts.random_access_range.h3"></a> 92 <span class="phrase"><a name="range.concepts.random_access_range.expression_semantics"></a></span><a class="link" href="random_access_range.html#range.concepts.random_access_range.expression_semantics">Expression 93 semantics</a> 94 </h5> 95<div class="informaltable"><table class="table"> 96<colgroup> 97<col> 98<col> 99<col> 100</colgroup> 101<thead><tr> 102<th> 103 <p> 104 Expression 105 </p> 106 </th> 107<th> 108 <p> 109 Semantics 110 </p> 111 </th> 112<th> 113 <p> 114 Postcondition 115 </p> 116 </th> 117</tr></thead> 118<tbody><tr> 119<td> 120 <p> 121 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">size</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span></code> 122 </p> 123 </td> 124<td> 125 <p> 126 Returns the size of the Range, that is, its number of elements. 127 Note <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">size</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span> 128 <span class="special">==</span> <span class="number">0u</span></code> 129 is equivalent to <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">empty</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span></code>. 130 </p> 131 </td> 132<td> 133 <p> 134 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">size</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span> 135 <span class="special">>=</span> <span class="number">0</span></code> 136 </p> 137 </td> 138</tr></tbody> 139</table></div> 140<h5> 141<a name="range.concepts.random_access_range.h4"></a> 142 <span class="phrase"><a name="range.concepts.random_access_range.complexity_guarantees"></a></span><a class="link" href="random_access_range.html#range.concepts.random_access_range.complexity_guarantees">Complexity 143 guarantees</a> 144 </h5> 145<p> 146 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">size</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span></code> completes in amortized constant time. 147 </p> 148<h5> 149<a name="range.concepts.random_access_range.h5"></a> 150 <span class="phrase"><a name="range.concepts.random_access_range.invariants"></a></span><a class="link" href="random_access_range.html#range.concepts.random_access_range.invariants">Invariants</a> 151 </h5> 152<div class="informaltable"><table class="table"> 153<colgroup> 154<col> 155<col> 156</colgroup> 157<thead><tr></tr></thead> 158<tbody><tr> 159<td> 160 <p> 161 Range size 162 </p> 163 </td> 164<td> 165 <p> 166 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">size</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span></code> 167 is equal to the <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">end</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span></code> - <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">begin</span><span class="special">(</span><span class="identifier">a</span><span class="special">)</span></code>. 168 </p> 169 </td> 170</tr></tbody> 171</table></div> 172</div> 173<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 174<td align="left"></td> 175<td align="right"><div class="copyright-footer">Copyright © 2003-2010 Thorsten Ottosen, 176 Neil Groves<p> 177 Distributed under the Boost Software License, Version 1.0. (See accompanying 178 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>) 179 </p> 180</div></td> 181</tr></table> 182<hr> 183<div class="spirit-nav"> 184<a accesskey="p" href="bidirectional_range.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><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="concept_checking.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 185</div> 186</body> 187</html> 188
