mpl/doc/refmanual/at-c.html
Steven Watanabe 6f63e9d0c6 Update generated html docs for MPL.
[SVN r64705]
2010-08-09 20:07:24 +00:00

136 lines
8.3 KiB
HTML

<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="generator" content="Docutils 0.7: http://docutils.sourceforge.net/" />
<title>The MPL Reference Manual: at_c</title>
<link rel="stylesheet" href="../style.css" type="text/css" />
</head>
<body class="docframe refmanual">
<table class="header"><tr class="header"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./at.html" class="navigation-link">Prev</a>&nbsp;<a href="./back.html" class="navigation-link">Next</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./at.html" class="navigation-link">Back</a>&nbsp;<a href="./back.html" class="navigation-link">Along</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./intrinsic-metafunctions.html" class="navigation-link">Up</a>&nbsp;<a href="../refmanual.html" class="navigation-link">Home</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./refmanual_toc.html" class="navigation-link">Full TOC</a></span></td>
<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="./at-c.html" class="navigation-link">at_c</a></td>
</tr></table><div class="header-separator"></div>
<div class="section" id="at-c">
<h1><a class="toc-backref" href="./intrinsic-metafunctions.html#id1426">at_c</a></h1>
<div class="section" id="id185">
<h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3>
<pre class="literal-block">
template&lt;
typename Sequence
, long n
&gt;
struct <a href="./at-c.html" class="identifier">at_c</a>
{
typedef <em>unspecified</em> type;
};
</pre>
</div>
<div class="section" id="id186">
<h3><a class="subsection-title" href="#description" name="description">Description</a></h3>
<p>Returns a type identical to the <tt class="literal"><span class="pre">n</span></tt>th element from the beginning of
the sequence. <tt class="literal"><span class="pre"><a href="./at-c.html" class="identifier">at_c</a>&lt;Sequence,n&gt;::type</span></tt> is a shorcut notation for
<tt class="literal"><span class="pre"><a href="./at.html" class="identifier">at</a>&lt;</span> <span class="pre">Sequence,</span> <span class="pre"><a href="./long.html" class="identifier">long_</a>&lt;n&gt;</span> <span class="pre">&gt;::type</span></tt>.</p>
</div>
<div class="section" id="id187">
<h3><a class="subsection-title" href="#header" name="header">Header</a></h3>
<pre class="literal-block">
#include &lt;<a href="../../../../boost/mpl/at.hpp" class="header">boost/mpl/at.hpp</a>&gt;
</pre>
</div>
<div class="section" id="id188">
<h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3>
<table border="1" class="docutils table">
<colgroup>
<col width="15%" />
<col width="36%" />
<col width="48%" />
</colgroup>
<thead valign="bottom">
<tr><th class="head">Parameter</th>
<th class="head">Requirement</th>
<th class="head">Description</th>
</tr>
</thead>
<tbody valign="top">
<tr><td><tt class="literal"><span class="pre">Sequence</span></tt></td>
<td><a class="reference internal" href="./forward-sequence.html">Forward Sequence</a></td>
<td>A sequence to be examined.</td>
</tr>
<tr><td><tt class="literal"><span class="pre">n</span></tt></td>
<td>A compile-time integral constant</td>
<td>An offset from the beginning of the sequence
specifying the element to be retrieved.</td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="id189">
<h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3>
<pre class="literal-block">
typedef <a href="./at-c.html" class="identifier">at_c</a>&lt;Sequence,n&gt;::type t;
</pre>
<table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first">A type</p>
</td>
</tr>
<tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">0</span> <span class="pre">&lt;=</span> <span class="pre">n</span> <span class="pre">&lt;</span> <span class="pre"><a href="./size.html" class="identifier">size</a>&lt;Sequence&gt;::value</span></tt></p>
</td>
</tr>
<tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first">Equivalent to</p>
<pre class="last literal-block">
typedef <a href="./at.html" class="identifier">at</a>&lt; Sequence, <a href="./long.html" class="identifier">long_</a>&lt;n&gt; &gt;::type t;
</pre>
</td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="id190">
<h3><a class="subsection-title" href="#complexity" name="complexity">Complexity</a></h3>
<table border="1" class="docutils table">
<colgroup>
<col width="47%" />
<col width="53%" />
</colgroup>
<thead valign="bottom">
<tr><th class="head">Sequence archetype</th>
<th class="head">Complexity</th>
</tr>
</thead>
<tbody valign="top">
<tr><td><a class="reference internal" href="./forward-sequence.html">Forward Sequence</a></td>
<td>Linear.</td>
</tr>
<tr><td><a class="reference internal" href="./random-access-sequence.html">Random Access Sequence</a></td>
<td>Amortized constant time.</td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="id191">
<h3><a class="subsection-title" href="#example" name="example">Example</a></h3>
<pre class="literal-block">
typedef <a href="./range-c.html" class="identifier">range_c</a>&lt;long,10,50&gt; range;
<a href="./assert-relation.html" class="identifier">BOOST_MPL_ASSERT_RELATION</a>( (<a href="./at-c.html" class="identifier">at_c</a>&lt; range,0 &gt;::type::value), ==, 10 );
<a href="./assert-relation.html" class="identifier">BOOST_MPL_ASSERT_RELATION</a>( (<a href="./at-c.html" class="identifier">at_c</a>&lt; range,10 &gt;::type::value), ==, 20 );
<a href="./assert-relation.html" class="identifier">BOOST_MPL_ASSERT_RELATION</a>( (<a href="./at-c.html" class="identifier">at_c</a>&lt; range,40 &gt;::type::value), ==, 50 );
</pre>
</div>
<div class="section" id="id192">
<h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3>
<p><a class="reference internal" href="./forward-sequence.html">Forward Sequence</a>, <a class="reference internal" href="./random-access-sequence.html">Random Access Sequence</a>, <a class="reference internal" href="./at.html">at</a>, <a class="reference internal" href="./front.html">front</a>, <a class="reference internal" href="./back.html">back</a></p>
<!-- Sequences/Intrinsic Metafunctions//back -->
</div>
</div>
<div class="footer-separator"></div>
<table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./at.html" class="navigation-link">Prev</a>&nbsp;<a href="./back.html" class="navigation-link">Next</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./at.html" class="navigation-link">Back</a>&nbsp;<a href="./back.html" class="navigation-link">Along</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./intrinsic-metafunctions.html" class="navigation-link">Up</a>&nbsp;<a href="../refmanual.html" class="navigation-link">Home</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./refmanual_toc.html" class="navigation-link">Full TOC</a></span></td>
<td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file 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>
</html>