| <?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: filter_view</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="./empty-sequence.html" class="navigation-link">Prev</a> <a href="./iterator-range.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./empty-sequence.html" class="navigation-link">Back</a> <a href="./iterator-range.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./views.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> |
| <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="./views.html" class="navigation-link">Views</a> / <a href="./filter-view.html" class="navigation-link">filter_view</a></td> |
| </tr></table><div class="header-separator"></div> |
| <div class="section" id="filter-view"> |
| <h1><a class="toc-backref" href="./views.html#id1418">filter_view</a></h1> |
| <div class="section" id="id126"> |
| <h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> |
| <pre class="literal-block"> |
| template< |
| typename Sequence |
| , typename Pred |
| > |
| struct <a href="./filter-view.html" class="identifier">filter_view</a> |
| { |
| // <em>unspecified</em> |
| // <em>...</em> |
| }; |
| </pre> |
| </div> |
| <div class="section" id="id127"> |
| <h3><a class="subsection-title" href="#description" name="description">Description</a></h3> |
| <p>A view into a subset of <tt class="literal"><span class="pre">Sequence</span></tt>'s elements satisfying the predicate <tt class="literal"><span class="pre">Pred</span></tt>.</p> |
| </div> |
| <div class="section" id="id128"> |
| <h3><a class="subsection-title" href="#header" name="header">Header</a></h3> |
| <pre class="literal-block"> |
| #include <<a href="../../../../boost/mpl/filter_view.hpp" class="header">boost/mpl/filter_view.hpp</a>> |
| </pre> |
| </div> |
| <div class="section" id="id129"> |
| <h3><a class="subsection-title" href="#model-of" name="model-of">Model of</a></h3> |
| <ul class="simple"> |
| <li><a class="reference internal" href="./forward-sequence.html">Forward Sequence</a></li> |
| </ul> |
| </div> |
| <div class="section" id="parameters"> |
| <h3>Parameters</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 wrap.</td> |
| </tr> |
| <tr><td><tt class="literal"><span class="pre">Pred</span></tt></td> |
| <td>Unary <a class="reference internal" href="./lambda-expression.html">Lambda Expression</a></td> |
| <td>A filtering predicate.</td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id130"> |
| <h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> |
| <p>Semantics of an expression is defined only where it differs from, or is not |
| defined in <a class="reference internal" href="./forward-sequence.html">Forward Sequence</a>.</p> |
| <p>In the following table, <tt class="literal"><span class="pre">v</span></tt> is an instance of <tt class="literal"><span class="pre"><a href="./filter-view.html" class="identifier">filter_view</a></span></tt>, <tt class="literal"><span class="pre">s</span></tt> is an arbitrary |
| <a class="reference internal" href="./forward-sequence.html">Forward Sequence</a>, <tt class="literal"><span class="pre">pred</span></tt> is an unary <a class="reference internal" href="./lambda-expression.html">Lambda Expression</a>.</p> |
| <table border="1" class="docutils table"> |
| <colgroup> |
| <col width="40%" /> |
| <col width="60%" /> |
| </colgroup> |
| <thead valign="bottom"> |
| <tr><th class="head">Expression</th> |
| <th class="head">Semantics</th> |
| </tr> |
| </thead> |
| <tbody valign="top"> |
| <tr><td><pre class="first last literal-block"> |
| <a href="./filter-view.html" class="identifier">filter_view</a><s,pred> |
| <a href="./filter-view.html" class="identifier">filter_view</a><s,pred>::type |
| </pre> |
| </td> |
| <td>A lazy <a class="reference internal" href="./forward-sequence.html">Forward Sequence</a> sequence of all the elements in |
| the range [<tt class="literal"><span class="pre"><a href="./begin.html" class="identifier">begin</a><s>::type</span></tt>, <tt class="literal"><span class="pre"><a href="./end.html" class="identifier">end</a><s>::type</span></tt>) that satisfy the predicate |
| <tt class="literal"><span class="pre">pred</span></tt>.</td> |
| </tr> |
| <tr><td><tt class="literal"><span class="pre"><a href="./size.html" class="identifier">size</a><v>::type</span></tt></td> |
| <td>The size of <tt class="literal"><span class="pre">v</span></tt>; |
| <tt class="literal"><span class="pre"><a href="./size.html" class="identifier">size</a><v>::value</span> <span class="pre">==</span> <span class="pre"><a href="./count-if.html" class="identifier">count_if</a><s,pred>::value</span></tt>; |
| linear complexity; see <a class="reference internal" href="./forward-sequence.html">Forward Sequence</a>.</td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id131"> |
| <h3><a class="subsection-title" href="#example" name="example">Example</a></h3> |
| <p>Find the largest floating type in a sequence.</p> |
| <pre class="literal-block"> |
| typedef <a href="./vector.html" class="identifier">vector</a><int,float,long,float,char[50],long double,char> types; |
| typedef <a href="./max-element.html" class="identifier">max_element</a>< |
| <a href="./transform-view.html" class="identifier">transform_view</a>< <a href="./filter-view.html" class="identifier">filter_view</a>< types,boost::is_float<_> >, size_of<_> > |
| >::type iter; |
| |
| <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< <a href="./deref.html" class="identifier">deref</a><iter::base>::type, long double > )); |
| </pre> |
| </div> |
| <div class="section" id="id132"> |
| <h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> |
| <p><a class="reference internal" href="./sequences.html">Sequences</a>, <a class="reference internal" href="./views.html">Views</a>, <a class="reference internal" href="./transform-view.html">transform_view</a>, <a class="reference internal" href="./joint-view.html">joint_view</a>, <a class="reference internal" href="./zip-view.html">zip_view</a>, <a class="reference internal" href="./iterator-range.html">iterator_range</a></p> |
| <!-- Sequences/Views//iterator_range --> |
| </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="./empty-sequence.html" class="navigation-link">Prev</a> <a href="./iterator-range.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./empty-sequence.html" class="navigation-link">Back</a> <a href="./iterator-range.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./views.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> |
| <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> |
