1<?xml version="1.0" encoding="utf-8" ?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> 4<head> 5<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 6<meta name="generator" content="Docutils 0.7: http://docutils.sourceforge.net/" /> 7<title>The MPL Reference Manual: next</title> 8<link rel="stylesheet" href="../style.css" type="text/css" /> 9</head> 10<body class="docframe refmanual"> 11<table class="header"><tr class="header"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./distance.html" class="navigation-link">Prev</a> <a href="./prior.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./distance.html" class="navigation-link">Back</a> <a href="./prior.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./iterator-metafunctions.html" class="navigation-link">Up</a> <a href="../refmanual.html" class="navigation-link">Home</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./refmanual_toc.html" class="navigation-link">Full TOC</a></span></td> 12<td class="header-group page-location"><a href="../refmanual.html" class="navigation-link">Front Page</a> / <a href="./iterators.html" class="navigation-link">Iterators</a> / <a href="./iterator-metafunctions.html" class="navigation-link">Iterator Metafunctions</a> / <a href="./next.html" class="navigation-link">next</a></td> 13</tr></table><div class="header-separator"></div> 14<div class="section" id="next"> 15<h1><a class="toc-backref" href="./iterator-metafunctions.html#id1456">next</a></h1> 16<div class="section" id="id421"> 17<h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> 18<pre class="literal-block"> 19template< 20 typename Iterator 21 > 22struct <a href="./next.html" class="identifier">next</a> 23{ 24 typedef <em>unspecified</em> type; 25}; 26</pre> 27</div> 28<div class="section" id="id422"> 29<h3><a class="subsection-title" href="#description" name="description">Description</a></h3> 30<p>Returns the next iterator in the sequence. [<em>Note:</em> <tt class="literal"><span class="pre"><a href="./next.html" class="identifier">next</a></span></tt> has a number of 31overloaded meanings, depending on the type of its argument. For instance, 32if <tt class="literal"><span class="pre">X</span></tt> is an <a class="reference internal" href="./integral-constant.html">Integral Constant</a>, <tt class="literal"><span class="pre"><a href="./next.html" class="identifier">next</a><X></span></tt> returns an incremented 33<a class="reference internal" href="./integral-constant.html">Integral Constant</a> of the same type. The following specification is 34iterator-specific. Please refer to the corresponding concept's 35documentation for the details of the alternative semantics — <em>end note</em>].</p> 36</div> 37<div class="section" id="id423"> 38<h3><a class="subsection-title" href="#header" name="header">Header</a></h3> 39<pre class="literal-block"> 40#include <<a href="../../../../boost/mpl/next_prior.hpp" class="header">boost/mpl/next_prior.hpp</a>> 41</pre> 42</div> 43<div class="section" id="id424"> 44<h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3> 45<table border="1" class="docutils table"> 46<colgroup> 47<col width="19%" /> 48<col width="35%" /> 49<col width="45%" /> 50</colgroup> 51<thead valign="bottom"> 52<tr><th class="head">Parameter</th> 53<th class="head">Requirement</th> 54<th class="head">Description</th> 55</tr> 56</thead> 57<tbody valign="top"> 58<tr><td><tt class="literal"><span class="pre">Iterator</span></tt></td> 59<td><a class="reference internal" href="./forward-iterator.html">Forward Iterator</a>.</td> 60<td>An iterator to increment.</td> 61</tr> 62</tbody> 63</table> 64</div> 65<div class="section" id="id425"> 66<h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> 67<p>For any <a class="reference internal" href="./forward-iterator.html">Forward Iterator</a>s <tt class="literal"><span class="pre">iter</span></tt>:</p> 68<pre class="literal-block"> 69typedef <a href="./next.html" class="identifier">next</a><iter>::type j; 70</pre> 71<table class="docutils field-list" frame="void" rules="none"> 72<col class="field-name" /> 73<col class="field-body" /> 74<tbody valign="top"> 75<tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first"><a class="reference internal" href="./forward-iterator.html">Forward Iterator</a>.</p> 76</td> 77</tr> 78<tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">iter</span></tt> is incrementable.</p> 79</td> 80</tr> 81<tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">j</span></tt> is an iterator pointing to the next element in the sequence, or 82is past-the-end. If <tt class="literal"><span class="pre">iter</span></tt> is a user-defined iterator, the 83library-provided default implementation is equivalent to</p> 84<pre class="last literal-block"> 85typedef iter::<a href="./next.html" class="identifier">next</a> j; 86</pre> 87</td> 88</tr> 89</tbody> 90</table> 91</div> 92<div class="section" id="id426"> 93<h3><a class="subsection-title" href="#complexity" name="complexity">Complexity</a></h3> 94<p>Amortized constant time.</p> 95</div> 96<div class="section" id="id427"> 97<h3><a class="subsection-title" href="#example" name="example">Example</a></h3> 98<pre class="literal-block"> 99typedef <a href="./vector-c.html" class="identifier">vector_c</a><int,1> v; 100typedef <a href="./begin.html" class="identifier">begin</a><v>::type first; 101typedef <a href="./end.html" class="identifier">end</a><v>::type last; 102 103<a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< <a href="./next.html" class="identifier">next</a><first>::type, last > )); 104</pre> 105</div> 106<div class="section" id="id428"> 107<h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> 108<p><a class="reference internal" href="./iterators.html">Iterators</a>, <a class="reference internal" href="./begin.html">begin</a> / <a class="reference internal" href="./end.html">end</a>, <a class="reference internal" href="./prior.html">prior</a>, <a class="reference internal" href="./deref.html">deref</a></p> 109<!-- Iterators/Iterator Metafunctions//prior |40 --> 110</div> 111</div> 112 113<div class="footer-separator"></div> 114<table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./distance.html" class="navigation-link">Prev</a> <a href="./prior.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./distance.html" class="navigation-link">Back</a> <a href="./prior.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./iterator-metafunctions.html" class="navigation-link">Up</a> <a href="../refmanual.html" class="navigation-link">Home</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./refmanual_toc.html" class="navigation-link">Full TOC</a></span></td> 115<td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div> 116Distributed under the Boost Software License, Version 1.0. (See accompanying 117file LICENSE_1_0.txt or copy at <a class="reference external" href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)</div></td></tr></table></body> 118</html> 119