forked from boostorg/fusion
256 lines
14 KiB
HTML
256 lines
14 KiB
HTML
<html>
|
||
<head>
|
||
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
|
||
<title>Random
|
||
Access Sequence</title>
|
||
<link rel="stylesheet" href="../../../boostbook.css" type="text/css">
|
||
<meta name="generator" content="DocBook XSL Stylesheets V1.66.1">
|
||
<link rel="start" href="../../../index.html" title="Chapter 1. Fusion 2.0">
|
||
<link rel="up" href="../concepts.html" title="Concepts">
|
||
<link rel="prev" href="bidirectional_sequence.html" title="Bidirectional
|
||
Sequence">
|
||
<link rel="next" href="associative_sequence.html" title="Associative
|
||
Sequence">
|
||
</head>
|
||
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
|
||
<table cellpadding="2" width="100%">
|
||
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td>
|
||
<td align="center"><a href="../../../../../../../index.htm">Home</a></td>
|
||
<td align="center"><a href="../../../../../../libraries.htm">Libraries</a></td>
|
||
<td align="center"><a href="../../../../../../../people/people.htm">People</a></td>
|
||
<td align="center"><a href="../../../../../../../more/faq.htm">FAQ</a></td>
|
||
<td align="center"><a href="../../../../../../../more/index.htm">More</a></td>
|
||
</table>
|
||
<hr>
|
||
<div class="spirit-nav">
|
||
<a accesskey="p" href="bidirectional_sequence.html"><img src="../../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><img src="../../../images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../images/home.png" alt="Home"></a><a accesskey="n" href="associative_sequence.html"><img src="../../../images/next.png" alt="Next"></a>
|
||
</div>
|
||
<div class="section" lang="en">
|
||
<div class="titlepage"><div><div><h4 class="title">
|
||
<a name="fusion.sequences.concepts.random_access_sequence"></a><a href="random_access_sequence.html" title="Random
|
||
Access Sequence">Random
|
||
Access Sequence</a></h4></div></div></div>
|
||
<a name="fusion.sequences.concepts.random_access_sequence.description"></a><h5>
|
||
<a name="id478915"></a>
|
||
<a href="random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.description">Description</a>
|
||
</h5>
|
||
<p>
|
||
A Random Access Sequence is a <a href="bidirectional_sequence.html" title="Bidirectional
|
||
Sequence">Bidirectional
|
||
Sequence</a> whose iterators model <a href="../../iterators/concepts/random_access_iterator.html" title="Random
|
||
Access Iterator">Random
|
||
Access Iterator</a>. It guarantees constant time access to arbitrary
|
||
sequence elements.
|
||
</p>
|
||
<a name="fusion.sequences.concepts.random_access_sequence.refinement_of"></a><h5>
|
||
<a name="id478967"></a>
|
||
<a href="random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.refinement_of">Refinement
|
||
of</a>
|
||
</h5>
|
||
<p>
|
||
<a href="bidirectional_sequence.html" title="Bidirectional
|
||
Sequence">Bidirectional
|
||
Sequence</a>
|
||
</p>
|
||
<div class="variablelist">
|
||
<p class="title"><b>Notation</b></p>
|
||
<dl>
|
||
<dt><span class="term"><tt class="computeroutput"><span class="identifier">s</span></tt></span></dt>
|
||
<dd>
|
||
A Random Access Sequence
|
||
</dd>
|
||
<dt><span class="term"><tt class="computeroutput"><span class="identifier">S</span></tt></span></dt>
|
||
<dd>
|
||
A Random Access Sequence type
|
||
</dd>
|
||
<dt><span class="term"><tt class="computeroutput"><span class="identifier">N</span></tt></span></dt>
|
||
<dd>
|
||
An integral constant
|
||
</dd>
|
||
<dt><span class="term"><tt class="computeroutput"><span class="identifier">o</span></tt></span></dt>
|
||
<dd>
|
||
An arbitrary object
|
||
</dd>
|
||
<dt><span class="term"><tt class="computeroutput"><span class="identifier">e</span></tt></span></dt>
|
||
<dd>
|
||
A Sequence element
|
||
</dd>
|
||
</dl>
|
||
</div>
|
||
<a name="fusion.sequences.concepts.random_access_sequence.valid_expressions"></a><h5>
|
||
<a name="id479103"></a>
|
||
<a href="random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.valid_expressions">Valid
|
||
Expressions</a>
|
||
</h5>
|
||
<p>
|
||
In addition to the requirements defined in <a href="bidirectional_sequence.html" title="Bidirectional
|
||
Sequence">Bidirectional
|
||
Sequence</a>, for any Random Access Sequence the following must be met:
|
||
</p>
|
||
<div class="informaltable">
|
||
<h4>
|
||
<a name="id479141"></a>
|
||
</h4>
|
||
<table class="table">
|
||
<colgroup>
|
||
<col>
|
||
<col>
|
||
<col>
|
||
<col>
|
||
</colgroup>
|
||
<thead><tr>
|
||
<th>Expression</th>
|
||
<th>Return type</th>
|
||
<th>Type Requirements</th>
|
||
<th>Runtime
|
||
Complexity</th>
|
||
</tr></thead>
|
||
<tbody>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/functions/begin.html" title="begin"><tt class="computeroutput"><span class="identifier">begin</span></tt></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></tt></td>
|
||
<td><a href="../../iterators/concepts/random_access_iterator.html" title="Random
|
||
Access Iterator">Random
|
||
Access Iterator</a></td>
|
||
<td> </td>
|
||
<td>Constant</td>
|
||
</tr>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/functions/end.html" title="end"><tt class="computeroutput"><span class="identifier">end</span></tt></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></tt></td>
|
||
<td><a href="../../iterators/concepts/random_access_iterator.html" title="Random
|
||
Access Iterator">Random
|
||
Access Iterator</a></td>
|
||
<td> </td>
|
||
<td>Constant</td>
|
||
</tr>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/functions/at.html" title="at"><tt class="computeroutput"><span class="identifier">at</span></tt></a><span class="special"><</span><span class="identifier">N</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></tt></td>
|
||
<td>Any
|
||
type</td>
|
||
<td> </td>
|
||
<td>Constant</td>
|
||
</tr>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/functions/at.html" title="at"><tt class="computeroutput"><span class="identifier">at</span></tt></a><span class="special"><</span><span class="identifier">N</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span> <span class="special">=</span> <span class="identifier">o</span></tt></td>
|
||
<td>Any
|
||
type</td>
|
||
<td>
|
||
<tt class="computeroutput"><span class="identifier">s</span></tt>
|
||
is mutable and <tt class="computeroutput"><span class="identifier">e</span> <span class="special">=</span> <span class="identifier">o</span></tt>,
|
||
where <tt class="computeroutput"><span class="identifier">e</span></tt> is the first
|
||
element in the sequence, is a valid expression.</td>
|
||
<td>Constant</td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
</div>
|
||
<a name="fusion.sequences.concepts.random_access_sequence.result_type_expressions"></a><h5>
|
||
<a name="id479467"></a>
|
||
<a href="random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.result_type_expressions">Result
|
||
Type Expressions</a>
|
||
</h5>
|
||
<div class="informaltable">
|
||
<h4>
|
||
<a name="id479490"></a>
|
||
</h4>
|
||
<table class="table">
|
||
<colgroup>
|
||
<col>
|
||
<col>
|
||
</colgroup>
|
||
<thead><tr>
|
||
<th>Expression</th>
|
||
<th>Compile Time Complexity</th>
|
||
</tr></thead>
|
||
<tbody>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/metafunctions/begin.html" title="begin"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin</span></tt></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></tt></td>
|
||
<td>Amortized constant
|
||
time</td>
|
||
</tr>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/metafunctions/end.html" title="end"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">end</span></tt></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></tt></td>
|
||
<td>Amortized constant
|
||
time</td>
|
||
</tr>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/metafunctions/at.html" title="at"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at</span></tt></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">>::</span><span class="identifier">type</span></tt></td>
|
||
<td>Amortized constant
|
||
time</td>
|
||
</tr>
|
||
<tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/metafunctions/value_at.html" title="value_at"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_at</span></tt></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">>::</span><span class="identifier">type</span></tt></td>
|
||
<td>Amortized constant
|
||
time</td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
</div>
|
||
<p class="blurb">
|
||
<span class="inlinemediaobject"><img src="../../../images/note.png" alt="note"></span> <tt class="computeroutput"><a href="../intrinsics/metafunctions/at.html" title="at"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at</span></tt></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">></span></tt>
|
||
returns the actual type returned by <tt class="computeroutput"><a href="../intrinsics/functions/at.html" title="at"><tt class="computeroutput"><span class="identifier">at</span></tt></a><span class="special"><</span><span class="identifier">N</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></tt>. In
|
||
most cases, this is a reference. Hence, there is no way to know the exact
|
||
element type using <tt class="computeroutput"><a href="../intrinsics/metafunctions/at.html" title="at"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at</span></tt></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">></span></tt>.The
|
||
element at <tt class="computeroutput"><span class="identifier">N</span></tt> may actually
|
||
be a reference to begin with. For this purpose, you can use <tt class="computeroutput"><a href="../intrinsics/metafunctions/value_at.html" title="value_at"><tt class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_at</span></tt></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">></span></tt>.
|
||
</p>
|
||
<a name="fusion.sequences.concepts.random_access_sequence.expression_semantics"></a><h5>
|
||
<a name="id480042"></a>
|
||
<a href="random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.expression_semantics">Expression
|
||
Semantics</a>
|
||
</h5>
|
||
<p>
|
||
The semantics of an expression are defined only where they differ from,
|
||
or are not defined in <a href="bidirectional_sequence.html" title="Bidirectional
|
||
Sequence">Bidirectional
|
||
Sequence</a>.
|
||
</p>
|
||
<div class="informaltable">
|
||
<h4>
|
||
<a name="id480080"></a>
|
||
</h4>
|
||
<table class="table">
|
||
<colgroup>
|
||
<col>
|
||
<col>
|
||
</colgroup>
|
||
<thead><tr>
|
||
<th>Expression</th>
|
||
<th>Semantics</th>
|
||
</tr></thead>
|
||
<tbody><tr>
|
||
<td><tt class="computeroutput"><a href="../intrinsics/functions/at.html" title="at"><tt class="computeroutput"><span class="identifier">at</span></tt></a><span class="special"><</span><span class="identifier">N</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></tt></td>
|
||
<td>The
|
||
Nth element from the beginning of the sequence; see <a href="../intrinsics/functions/at.html" title="at"><tt class="computeroutput"><span class="identifier">at</span></tt></a>.</td>
|
||
</tr></tbody>
|
||
</table>
|
||
</div>
|
||
<a name="fusion.sequences.concepts.random_access_sequence.models"></a><h5>
|
||
<a name="id480186"></a>
|
||
<a href="random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.models">Models</a>
|
||
</h5>
|
||
<div class="itemizedlist"><ul type="disc">
|
||
<li><a href="../adapted/std__pair.html" title="std::pair"><tt class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></tt></a></li>
|
||
<li><a href="../adapted/boost__array.html" title="boost::array"><tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">array</span></tt></a></li>
|
||
<li><a href="../containers/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a></li>
|
||
<li>
|
||
<a href="../views/iterator_range.html" title="iterator_range"><tt class="computeroutput"><span class="identifier">iterator_range</span></tt></a>
|
||
(where adapted sequence is a Random Access Sequence)
|
||
</li>
|
||
<li>
|
||
<a href="../views/transform_view.html" title="transform_view"><tt class="computeroutput"><span class="identifier">transform_view</span></tt></a>
|
||
(where adapted sequence is a Random Access Sequence)
|
||
</li>
|
||
<li><a href="../views/reverse_view.html" title="reverse_view"><tt class="computeroutput"><span class="identifier">reverse_view</span></tt></a></li>
|
||
</ul></div>
|
||
</div>
|
||
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
|
||
<td align="left"></td>
|
||
<td align="right"><small>Copyright © 2001-2005 Joel de Guzman, Dan Marsden</small></td>
|
||
</tr></table>
|
||
<hr>
|
||
<div class="spirit-nav">
|
||
<a accesskey="p" href="bidirectional_sequence.html"><img src="../../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../concepts.html"><img src="../../../images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../images/home.png" alt="Home"></a><a accesskey="n" href="associative_sequence.html"><img src="../../../images/next.png" alt="Next"></a>
|
||
</div>
|
||
</body>
|
||
</html>
|