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| <div class="section"> |
| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="fusion.sequence.concepts.random_access_sequence"></a><a class="link" href="random_access_sequence.html" title="Random Access Sequence">Random |
| Access Sequence</a> |
| </h4></div></div></div> |
| <a name="fusion.sequence.concepts.random_access_sequence.description"></a><h6> |
| <a name="id874614"></a> |
| <a class="link" href="random_access_sequence.html#fusion.sequence.concepts.random_access_sequence.description">Description</a> |
| </h6> |
| <p> |
| A Random Access Sequence is a <a class="link" href="bidirectional_sequence.html" title="Bidirectional Sequence">Bidirectional |
| Sequence</a> whose iterators model <a class="link" href="../../iterator/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.sequence.concepts.random_access_sequence.refinement_of"></a><h6> |
| <a name="id874645"></a> |
| <a class="link" href="random_access_sequence.html#fusion.sequence.concepts.random_access_sequence.refinement_of">Refinement |
| of</a> |
| </h6> |
| <p> |
| <a class="link" 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"><code class="computeroutput"><span class="identifier">s</span></code></span></dt> |
| <dd><p> |
| A Random Access Sequence |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">S</span></code></span></dt> |
| <dd><p> |
| A Random Access Sequence type |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">N</span></code></span></dt> |
| <dd><p> |
| An <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL |
| Integral Constant</a> |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">o</span></code></span></dt> |
| <dd><p> |
| An arbitrary object |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">e</span></code></span></dt> |
| <dd><p> |
| A Sequence element |
| </p></dd> |
| </dl> |
| </div> |
| <a name="fusion.sequence.concepts.random_access_sequence.valid_expressions"></a><h6> |
| <a name="id874780"></a> |
| <a class="link" href="random_access_sequence.html#fusion.sequence.concepts.random_access_sequence.valid_expressions">Valid |
| Expressions</a> |
| </h6> |
| <p> |
| In addition to the requirements defined in <a class="link" href="bidirectional_sequence.html" title="Bidirectional Sequence">Bidirectional |
| Sequence</a>, for any Random Access Sequence the following must be met: |
| </p> |
| <div class="informaltable"><table class="table"> |
| <colgroup> |
| <col> |
| <col> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| Expression |
| </p> |
| </th> |
| <th> |
| <p> |
| Return type |
| </p> |
| </th> |
| <th> |
| <p> |
| Type Requirements |
| </p> |
| </th> |
| <th> |
| <p> |
| Runtime Complexity |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">begin</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <a class="link" href="../../iterator/concepts/random_access_iterator.html" title="Random Access Iterator">Random |
| Access Iterator</a> |
| </p> |
| </td> |
| <td> |
| </td> |
| <td> |
| <p> |
| Constant |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/end.html" title="end"><code class="computeroutput"><span class="identifier">end</span></code></a><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <a class="link" href="../../iterator/concepts/random_access_iterator.html" title="Random Access Iterator">Random |
| Access Iterator</a> |
| </p> |
| </td> |
| <td> |
| </td> |
| <td> |
| <p> |
| Constant |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/at.html" title="at"><code class="computeroutput"><span class="identifier">at</span></code></a><span class="special"><</span><span class="identifier">N</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Any type |
| </p> |
| </td> |
| <td> |
| </td> |
| <td> |
| <p> |
| Constant |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/at.html" title="at"><code class="computeroutput"><span class="identifier">at</span></code></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></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Any type |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">s</span></code> is mutable |
| and <code class="computeroutput"><span class="identifier">e</span> <span class="special">=</span> |
| <span class="identifier">o</span></code>, where <code class="computeroutput"><span class="identifier">e</span></code> is the first element in the |
| sequence, is a valid expression. |
| </p> |
| </td> |
| <td> |
| <p> |
| Constant |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| <a name="fusion.sequence.concepts.random_access_sequence.result_type_expressions"></a><h6> |
| <a name="id875128"></a> |
| <a class="link" href="random_access_sequence.html#fusion.sequence.concepts.random_access_sequence.result_type_expressions">Result |
| Type Expressions</a> |
| </h6> |
| <div class="informaltable"><table class="table"> |
| <colgroup> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| Expression |
| </p> |
| </th> |
| <th> |
| <p> |
| Compile Time Complexity |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/begin.html" title="begin"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">begin</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Amortized constant time |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/end.html" title="end"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">end</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">>::</span><span class="identifier">type</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Amortized constant time |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/at.html" title="at"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at</span></code></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></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Amortized constant time |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/value_at.html" title="value_at"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_at</span></code></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></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Amortized constant time |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| <div class="sidebar"> |
| <p class="title"><b></b></p> |
| <p> |
| <span class="inlinemediaobject"><img src="../../../images/note.png" alt="note"></span> <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/at.html" title="at"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">></span></code> returns the actual type returned by |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/at.html" title="at"><code class="computeroutput"><span class="identifier">at</span></code></a><span class="special"><</span><span class="identifier">N</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></code>. In |
| most cases, this is a reference. Hence, there is no way to know the exact |
| element type using <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/at.html" title="at"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">></span></code>.The element at <code class="computeroutput"><span class="identifier">N</span></code> |
| may actually be a reference to begin with. For this purpose, you can use |
| <code class="computeroutput"><a class="link" href="../intrinsic/metafunctions/value_at.html" title="value_at"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_at</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">N</span><span class="special">></span></code>. |
| </p> |
| </div> |
| <a name="fusion.sequence.concepts.random_access_sequence.expression_semantics"></a><h6> |
| <a name="id875580"></a> |
| <a class="link" href="random_access_sequence.html#fusion.sequence.concepts.random_access_sequence.expression_semantics">Expression |
| Semantics</a> |
| </h6> |
| <p> |
| The semantics of an expression are defined only where they differ from, |
| or are not defined in <a class="link" href="bidirectional_sequence.html" title="Bidirectional Sequence">Bidirectional |
| Sequence</a>. |
| </p> |
| <div class="informaltable"><table class="table"> |
| <colgroup> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| Expression |
| </p> |
| </th> |
| <th> |
| <p> |
| Semantics |
| </p> |
| </th> |
| </tr></thead> |
| <tbody><tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/at.html" title="at"><code class="computeroutput"><span class="identifier">at</span></code></a><span class="special"><</span><span class="identifier">N</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| The Nth element from the beginning of the sequence; see <a class="link" href="../intrinsic/functions/at.html" title="at"><code class="computeroutput"><span class="identifier">at</span></code></a>. |
| </p> |
| </td> |
| </tr></tbody> |
| </table></div> |
| <a name="fusion.sequence.concepts.random_access_sequence.models"></a><h6> |
| <a name="id875694"></a> |
| <a class="link" href="random_access_sequence.html#fusion.sequence.concepts.random_access_sequence.models">Models</a> |
| </h6> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <a class="link" href="../../adapted/std__pair.html" title="std::pair"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></code></a> |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../adapted/boost__array.html" title="boost::array"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">array</span></code></a> |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../container/vector.html" title="vector"><code class="computeroutput"><span class="identifier">vector</span></code></a> |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../view/reverse_view.html" title="reverse_view"><code class="computeroutput"><span class="identifier">reverse_view</span></code></a> |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../view/iterator_range.html" title="iterator_range"><code class="computeroutput"><span class="identifier">iterator_range</span></code></a> |
| (where adapted sequence is a Random Access Sequence) |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../view/transform_view.html" title="transform_view"><code class="computeroutput"><span class="identifier">transform_view</span></code></a> |
| (where adapted sequence is a Random Access Sequence) |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../view/zip_view.html" title="zip_view"><code class="computeroutput"><span class="identifier">zip_view</span></code></a> |
| (where adapted sequences are models of Random Access Sequence) |
| </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"><div class="copyright-footer">Copyright © 2001-2007 Joel de Guzman, Dan Marsden, Tobias |
| Schwinger<p> |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 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>) |
| </p> |
| </div></td> |
| </tr></table> |
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