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| <div class="titlepage"><div><div><h4 class="title"> |
| <a name="fusion.sequence.concepts.associative_sequence"></a><a class="link" href="associative_sequence.html" title="Associative Sequence">Associative |
| Sequence</a> |
| </h4></div></div></div> |
| <a name="fusion.sequence.concepts.associative_sequence.description"></a><h6> |
| <a name="id875856"></a> |
| <a class="link" href="associative_sequence.html#fusion.sequence.concepts.associative_sequence.description">Description</a> |
| </h6> |
| <p> |
| An Associative Sequence allows efficient retrieval of elements based on |
| keys. Like associative sequences in <a href="http://www.boost.org/libs/mpl/index.html" target="_top">MPL</a>, |
| and unlike associative containers in <a href="http://en.wikipedia.org/wiki/Standard_Template_Library" target="_top">STL</a>, |
| Fusion associative sequences have no implied ordering relation. Instead, |
| type identity is used to impose an equivalence relation on keys. |
| </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> |
| An Associative Sequence |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">S</span></code></span></dt> |
| <dd><p> |
| An Associative Sequence type |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">K</span></code></span></dt> |
| <dd><p> |
| An arbitrary <span class="emphasis"><em>key</em></span> type |
| </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.associative_sequence.valid_expressions"></a><h6> |
| <a name="id875995"></a> |
| <a class="link" href="associative_sequence.html#fusion.sequence.concepts.associative_sequence.valid_expressions">Valid |
| Expressions</a> |
| </h6> |
| <p> |
| For any Associative Sequence the following expressions must be valid: |
| </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/has_key.html" title="has_key"><code class="computeroutput"><span class="identifier">has_key</span></code></a><span class="special"><</span><span class="identifier">K</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL |
| Boolean Constant</a>. Convertible to bool. |
| </p> |
| </td> |
| <td> |
| </td> |
| <td> |
| <p> |
| Constant |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/at_key.html" title="at_key"><code class="computeroutput"><span class="identifier">at_key</span></code></a><span class="special"><</span><span class="identifier">K</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_key.html" title="at_key"><code class="computeroutput"><span class="identifier">at_key</span></code></a><span class="special"><</span><span class="identifier">K</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.associative_sequence.result_type_expressions"></a><h6> |
| <a name="id876292"></a> |
| <a class="link" href="associative_sequence.html#fusion.sequence.concepts.associative_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/has_key.html" title="has_key"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">has_key</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> |
| <span class="identifier">K</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_key.html" title="at_key"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at_key</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> |
| <span class="identifier">K</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_key.html" title="value_at_key"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_at_key</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">K</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_key.html" title="at_key"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at_key</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">K</span><span class="special">></span></code> returns the actual type returned by |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/at_key.html" title="at_key"><code class="computeroutput"><span class="identifier">at_key</span></code></a><span class="special"><</span><span class="identifier">K</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_key.html" title="at_key"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">at_key</span></code></a><span class="special"><</span><span class="identifier">S</span><span class="special">,</span> <span class="identifier">K</span><span class="special">></span></code>.The element at <code class="computeroutput"><span class="identifier">K</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_key.html" title="value_at_key"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">value_at_key</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.associative_sequence.expression_semantics"></a><h6> |
| <a name="id876700"></a> |
| <a class="link" href="associative_sequence.html#fusion.sequence.concepts.associative_sequence.expression_semantics">Expression |
| Semantics</a> |
| </h6> |
| <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/has_key.html" title="has_key"><code class="computeroutput"><span class="identifier">has_key</span></code></a><span class="special"><</span><span class="identifier">K</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| A boolean Integral Constant <code class="computeroutput"><span class="identifier">c</span></code> |
| such that <code class="computeroutput"><span class="identifier">c</span><span class="special">::</span><span class="identifier">value</span> <span class="special">==</span> |
| <span class="keyword">true</span></code> if and only if there |
| is one or more elements with the key <code class="computeroutput"><span class="identifier">k</span></code> |
| in <code class="computeroutput"><span class="identifier">s</span></code>; see <a class="link" href="../intrinsic/functions/has_key.html" title="has_key"><code class="computeroutput"><span class="identifier">has_key</span></code></a>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><a class="link" href="../intrinsic/functions/at_key.html" title="at_key"><code class="computeroutput"><span class="identifier">at_key</span></code></a><span class="special"><</span><span class="identifier">K</span><span class="special">>(</span><span class="identifier">s</span><span class="special">)</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| The element associated with the key <code class="computeroutput"><span class="identifier">K</span></code> |
| in the sequence <code class="computeroutput"><span class="identifier">s</span></code>; |
| 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.associative_sequence.models"></a><h6> |
| <a name="id876924"></a> |
| <a class="link" href="associative_sequence.html#fusion.sequence.concepts.associative_sequence.models">Models</a> |
| </h6> |
| <div class="itemizedlist"><ul class="itemizedlist" type="disc"> |
| <li class="listitem"> |
| <a class="link" href="../../container/set.html" title="set"><code class="computeroutput"><span class="identifier">set</span></code></a> |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../container/map.html" title="map"><code class="computeroutput"><span class="identifier">map</span></code></a> |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../view/filter_view.html" title="filter_view"><code class="computeroutput"><span class="identifier">filter_view</span></code></a> |
| (where adapted sequence is an <a class="link" href="associative_sequence.html" title="Associative Sequence">Associative |
| Sequence</a> and a <a class="link" href="forward_sequence.html" title="Forward Sequence">Forward |
| Sequence</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 iterators are <a class="link" href="../../iterator/concepts/associative_iterator.html" title="Associative Iterator">Associative |
| Iterator</a>s) |
| </li> |
| <li class="listitem"> |
| <a class="link" href="../../view/joint_view.html" title="joint_view"><code class="computeroutput"><span class="identifier">joint_view</span></code></a> |
| (where adapted sequences are <a class="link" href="associative_sequence.html" title="Associative Sequence">Associative |
| Sequence</a>s and <a class="link" href="forward_sequence.html" title="Forward Sequence">Forward |
| Sequence</a>s) |
| </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> |
| (where adapted sequence is an <a class="link" href="associative_sequence.html" title="Associative Sequence">Associative |
| Sequence</a> and a <a class="link" href="bidirectional_sequence.html" title="Bidirectional Sequence">Bidirectional |
| Sequence</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"><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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