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: erase</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="./end.html" class="navigation-link">Prev</a> <a href="./erase-key.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./end.html" class="navigation-link">Back</a> <a href="./erase-key.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./intrinsic-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="./sequences.html" class="navigation-link">Sequences</a> / <a href="./intrinsic-metafunctions.html" class="navigation-link">Intrinsic Metafunctions</a> / <a href="./erase.html" class="navigation-link">erase</a></td> 13</tr></table><div class="header-separator"></div> 14<div class="section" id="erase"> 15<h1><a class="toc-backref" href="./intrinsic-metafunctions.html#id1432">erase</a></h1> 16<div class="section" id="id238"> 17<h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> 18<pre class="literal-block"> 19template< 20 typename Sequence 21 , typename First 22 , typename Last = <em>unspecified</em> 23 > 24struct <a href="./erase.html" class="identifier">erase</a> 25{ 26 typedef <em>unspecified</em> type; 27}; 28</pre> 29</div> 30<div class="section" id="id239"> 31<h3><a class="subsection-title" href="#description" name="description">Description</a></h3> 32<p><tt class="literal"><span class="pre"><a href="./erase.html" class="identifier">erase</a></span></tt> performs a removal of one or more adjacent elements in the sequence 33starting from an arbitrary position.</p> 34</div> 35<div class="section" id="id240"> 36<h3><a class="subsection-title" href="#header" name="header">Header</a></h3> 37<pre class="literal-block"> 38#include <<a href="../../../../boost/mpl/erase.hpp" class="header">boost/mpl/erase.hpp</a>> 39</pre> 40</div> 41<div class="section" id="id241"> 42<h3><a class="subsection-title" href="#model-of" name="model-of">Model of</a></h3> 43<p><a class="reference internal" href="./tag-dispatched-metafunction.html">Tag Dispatched Metafunction</a></p> 44</div> 45<div class="section" id="id242"> 46<h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3> 47<table border="1" class="docutils table"> 48<colgroup> 49<col width="15%" /> 50<col width="36%" /> 51<col width="48%" /> 52</colgroup> 53<thead valign="bottom"> 54<tr><th class="head">Parameter</th> 55<th class="head">Requirement</th> 56<th class="head">Description</th> 57</tr> 58</thead> 59<tbody valign="top"> 60<tr><td><tt class="literal"><span class="pre">Sequence</span></tt></td> 61<td><a class="reference internal" href="./extensible-sequence.html">Extensible Sequence</a> or 62<a class="reference internal" href="./extensible-associative-sequence.html">Extensible Associative Sequence</a></td> 63<td>A sequence to erase from.</td> 64</tr> 65<tr><td><tt class="literal"><span class="pre">First</span></tt></td> 66<td><a class="reference internal" href="./forward-iterator.html">Forward Iterator</a></td> 67<td>An iterator to the beginning of the range to 68be erased.</td> 69</tr> 70<tr><td><tt class="literal"><span class="pre">Last</span></tt></td> 71<td><a class="reference internal" href="./forward-iterator.html">Forward Iterator</a></td> 72<td>An iterator past-the-end of the range to be 73erased.</td> 74</tr> 75</tbody> 76</table> 77</div> 78<div class="section" id="id243"> 79<h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> 80<div class="expression-semantics compound"> 81<p class="compound-first">For any <a class="reference internal" href="./extensible-sequence.html">Extensible Sequence</a> <tt class="literal"><span class="pre">s</span></tt>, and iterators <tt class="literal"><span class="pre">pos</span></tt>, <tt class="literal"><span class="pre">first</span></tt> and <tt class="literal"><span class="pre">last</span></tt> into <tt class="literal"><span class="pre">s</span></tt>:</p> 82<pre class="compound-middle literal-block"> 83typedef <a href="./erase.html" class="identifier">erase</a><s,first,last>::type r; 84</pre> 85<table class="compound-middle docutils field-list" frame="void" rules="none"> 86<col class="field-name" /> 87<col class="field-body" /> 88<tbody valign="top"> 89<tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first"><a class="reference internal" href="./extensible-sequence.html">Extensible Sequence</a>.</p> 90</td> 91</tr> 92<tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">[first,last)</span></tt> is a valid range in <tt class="literal"><span class="pre">s</span></tt>.</p> 93</td> 94</tr> 95<tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">r</span></tt> is a new sequence, <a class="reference internal" href="./terminology.html#concept-identical">concept-identical</a> to <tt class="literal"><span class="pre">s</span></tt>, of the following elements: 96[<tt class="literal"><span class="pre"><a href="./begin.html" class="identifier">begin</a><s>::type</span></tt>, <tt class="literal"><span class="pre">pos</span></tt>), [<tt class="literal"><span class="pre">last</span></tt>, <tt class="literal"><span class="pre"><a href="./end.html" class="identifier">end</a><s>::type</span></tt>).</p> 97</td> 98</tr> 99<tr class="field"><th class="field-name">Postcondition:</th><td class="field-body"><p class="first">The relative order of the elements in <tt class="literal"><span class="pre">r</span></tt> is the same as in <tt class="literal"><span class="pre">s</span></tt>;</p> 100<pre class="last literal-block"> 101<a href="./size.html" class="identifier">size</a><r>::value == <a href="./size.html" class="identifier">size</a><s>::value - <a href="./distance.html" class="identifier">distance</a><first,last>::value 102</pre> 103</td> 104</tr> 105</tbody> 106</table> 107<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ --> 108<pre class="compound-middle literal-block"> 109typedef <a href="./erase.html" class="identifier">erase</a><s,pos>::type r; 110</pre> 111<table class="compound-last docutils field-list" frame="void" rules="none"> 112<col class="field-name" /> 113<col class="field-body" /> 114<tbody valign="top"> 115<tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first"><a class="reference internal" href="./extensible-sequence.html">Extensible Sequence</a>.</p> 116</td> 117</tr> 118<tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">pos</span></tt> is a dereferenceable iterator in <tt class="literal"><span class="pre">s</span></tt>.</p> 119</td> 120</tr> 121<tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first">Equivalent to</p> 122<pre class="last literal-block"> 123typedef <a href="./erase.html" class="identifier">erase</a>< s,pos,<a href="./next.html" class="identifier">next</a><pos>::type >::type r; 124</pre> 125</td> 126</tr> 127</tbody> 128</table> 129</div> 130<div class="expression-semantics compound"> 131<p class="compound-first">For any <a class="reference internal" href="./extensible-associative-sequence.html">Extensible Associative Sequence</a> <tt class="literal"><span class="pre">s</span></tt>, and iterator <tt class="literal"><span class="pre">pos</span></tt> into <tt class="literal"><span class="pre">s</span></tt>:</p> 132<pre class="compound-middle literal-block"> 133typedef <a href="./erase.html" class="identifier">erase</a><s,pos>::type r; 134</pre> 135<table class="compound-last docutils field-list" frame="void" rules="none"> 136<col class="field-name" /> 137<col class="field-body" /> 138<tbody valign="top"> 139<tr class="field"><th class="field-name">Return type:</th><td class="field-body"><a class="reference internal" href="./extensible-sequence.html">Extensible Sequence</a>.</td> 140</tr> 141<tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><tt class="literal"><span class="pre">pos</span></tt> is a dereferenceable iterator to <tt class="literal"><span class="pre">s</span></tt>.</td> 142</tr> 143<tr class="field"><th class="field-name">Semantics:</th><td class="field-body">Erases the element at a specific position <tt class="literal"><span class="pre">pos</span></tt>; equivalent to 144<tt class="literal"><span class="pre"><a href="./erase-key.html" class="identifier">erase_key</a><s,</span> <span class="pre"><a href="./deref.html" class="identifier">deref</a><pos>::type</span> <span class="pre">>::type</span></tt>.</td> 145</tr> 146<tr class="field"><th class="field-name">Postcondition:</th><td class="field-body"><tt class="literal"><span class="pre"><a href="./size.html" class="identifier">size</a><r>::value</span> <span class="pre">==</span> <span class="pre"><a href="./size.html" class="identifier">size</a><s>::value</span> <span class="pre">-</span> <span class="pre">1</span></tt>.</td> 147</tr> 148</tbody> 149</table> 150</div> 151</div> 152<div class="section" id="id244"> 153<h3><a class="subsection-title" href="#complexity" name="complexity">Complexity</a></h3> 154<table border="1" class="docutils table"> 155<colgroup> 156<col width="45%" /> 157<col width="55%" /> 158</colgroup> 159<thead valign="bottom"> 160<tr><th class="head">Sequence archetype</th> 161<th class="head">Complexity (the range form)</th> 162</tr> 163</thead> 164<tbody valign="top"> 165<tr><td><a class="reference internal" href="./extensible-associative-sequence.html">Extensible Associative Sequence</a></td> 166<td>Amortized constant time.</td> 167</tr> 168<tr><td><a class="reference internal" href="./extensible-sequence.html">Extensible Sequence</a></td> 169<td>Quadratic in the worst case, linear at best.</td> 170</tr> 171</tbody> 172</table> 173</div> 174<div class="section" id="id245"> 175<h3><a class="subsection-title" href="#example" name="example">Example</a></h3> 176<pre class="literal-block"> 177typedef <a href="./vector-c.html" class="identifier">vector_c</a><int,1,0,5,1,7,5,0,5> values; 178typedef <a href="./find.html" class="identifier">find</a>< values, <a href="./integral-c.html" class="identifier">integral_c</a><int,7> >::type pos; 179typedef <a href="./erase.html" class="identifier">erase</a><values,pos>::type result; 180 181<a href="./assert-relation.html" class="identifier">BOOST_MPL_ASSERT_RELATION</a>( <a href="./size.html" class="identifier">size</a><result>::value, ==, 7 ); 182 183typedef <a href="./find.html" class="identifier">find</a><result, <a href="./integral-c.html" class="identifier">integral_c</a><int,7> >::type iter; 184<a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< iter, <a href="./end.html" class="identifier">end</a><result>::type > )); 185</pre> 186</div> 187<div class="section" id="id246"> 188<h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> 189<p><a class="reference internal" href="./extensible-sequence.html">Extensible Sequence</a>, <a class="reference internal" href="./extensible-associative-sequence.html">Extensible Associative Sequence</a>, <a class="reference internal" href="./erase-key.html">erase_key</a>, <a class="reference internal" href="./pop-front.html">pop_front</a>, <a class="reference internal" href="./pop-back.html">pop_back</a>, <a class="reference internal" href="./insert.html">insert</a></p> 190<!-- Sequences/Intrinsic Metafunctions//erase_key --> 191</div> 192</div> 193 194<div class="footer-separator"></div> 195<table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./end.html" class="navigation-link">Prev</a> <a href="./erase-key.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./end.html" class="navigation-link">Back</a> <a href="./erase-key.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./intrinsic-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> 196<td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div> 197Distributed under the Boost Software License, Version 1.0. 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