| <?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: for_each</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="./runtime-algorithms.html" class="navigation-link">Prev</a> <a href="./metafunctions.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group">Back Along</span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./runtime-algorithms.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="./algorithms.html" class="navigation-link">Algorithms</a> / <a href="./runtime-algorithms.html" class="navigation-link">Runtime Algorithms</a> / <a href="./for-each.html" class="navigation-link">for_each</a></td> |
| </tr></table><div class="header-separator"></div> |
| <div class="section" id="for-each"> |
| <h1><a class="toc-backref" href="./runtime-algorithms.html#id1509">for_each</a></h1> |
| <div class="section" id="id812"> |
| <h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> |
| <pre class="literal-block"> |
| template< |
| typename Sequence |
| , typename F |
| > |
| void <a href="./for-each.html" class="identifier">for_each</a>( F f ); |
| |
| template< |
| typename Sequence |
| , typename TransformOp |
| , typename F |
| > |
| void <a href="./for-each.html" class="identifier">for_each</a>( F f ); |
| </pre> |
| </div> |
| <div class="section" id="id813"> |
| <h3><a class="subsection-title" href="#description" name="description">Description</a></h3> |
| <p><tt class="literal"><span class="pre"><a href="./for-each.html" class="identifier">for_each</a></span></tt> is a family of overloaded function templates:</p> |
| <ul class="simple"> |
| <li><tt class="literal"><span class="pre"><a href="./for-each.html" class="identifier">for_each</a><Sequence>(</span> <span class="pre">f</span> <span class="pre">)</span></tt> applies the runtime function object |
| <tt class="literal"><span class="pre">f</span></tt> to every element in the [<tt class="literal"><span class="pre"><a href="./begin.html" class="identifier">begin</a><Sequence>::type</span></tt>, <tt class="literal"><span class="pre"><a href="./end.html" class="identifier">end</a><Sequence>::type</span></tt>) range.</li> |
| <li><tt class="literal"><span class="pre"><a href="./for-each.html" class="identifier">for_each</a><Sequence,TransformOp>(</span> <span class="pre">f</span> <span class="pre">)</span></tt> applies the runtime function |
| object <tt class="literal"><span class="pre">f</span></tt> to the result of the transformation <tt class="literal"><span class="pre">TransformOp</span></tt> of |
| every element in the [<tt class="literal"><span class="pre"><a href="./begin.html" class="identifier">begin</a><Sequence>::type</span></tt>, <tt class="literal"><span class="pre"><a href="./end.html" class="identifier">end</a><Sequence>::type</span></tt>) range.</li> |
| </ul> |
| </div> |
| <div class="section" id="id814"> |
| <h3><a class="subsection-title" href="#header" name="header">Header</a></h3> |
| <pre class="literal-block"> |
| #include <<a href="../../../../boost/mpl/for_each.hpp" class="header">boost/mpl/for_each.hpp</a>> |
| </pre> |
| </div> |
| <div class="section" id="id815"> |
| <h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3> |
| <table border="1" class="docutils table"> |
| <colgroup> |
| <col width="21%" /> |
| <col width="39%" /> |
| <col width="39%" /> |
| </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 iterate.</td> |
| </tr> |
| <tr><td><tt class="literal"><span class="pre">TransformOp</span></tt></td> |
| <td><a class="reference internal" href="./lambda-expression.html">Lambda Expression</a></td> |
| <td>A transformation.</td> |
| </tr> |
| <tr><td><tt class="literal"><span class="pre">f</span></tt></td> |
| <td>An <a class="reference external" href="http://www.sgi.com/tech/stl/UnaryFunction.html" target="_top">unary function object</a></td> |
| <td>A runtime operation to apply.</td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id816"> |
| <h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> |
| <p>For any <a class="reference internal" href="./forward-sequence.html">Forward Sequence</a> <tt class="literal"><span class="pre">s</span></tt>, <a class="reference internal" href="./lambda-expression.html">Lambda Expression</a> <tt class="literal"><span class="pre">op</span></tt> , and an |
| <a class="reference external" href="http://www.sgi.com/tech/stl/UnaryFunction.html" target="_top">unary function object</a> <tt class="literal"><span class="pre">f</span></tt>:</p> |
| <pre class="literal-block"> |
| <a href="./for-each.html" class="identifier">for_each</a><s>( f ); |
| </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"><tt class="literal"><span class="pre">void</span></tt></p> |
| </td> |
| </tr> |
| <tr class="field"><th class="field-name">Postcondition:</th><td class="field-body"><p class="first">Equivalent to</p> |
| <pre class="literal-block"> |
| typedef <a href="./begin.html" class="identifier">begin</a><Sequence>::type i<sub>1</sub>; |
| <a class="reference external" href="http://www.boost.org/libs/utility/value_init.htm" target="_top">value_initialized</a>< <a href="./deref.html" class="identifier">deref</a><i<sub>1</sub>>::type > x<sub>1</sub>; |
| f(boost::get(x<sub>1</sub>)); |
| |
| typedef <a href="./next.html" class="identifier">next</a><i<sub>1</sub>>::type i<sub>2</sub>; |
| <a class="reference external" href="http://www.boost.org/libs/utility/value_init.htm" target="_top">value_initialized</a>< <a href="./deref.html" class="identifier">deref</a><i<sub>2</sub>>::type > x<sub>2</sub>; |
| f(boost::get(x<sub>2</sub>)); |
| <em>...</em> |
| <a class="reference external" href="http://www.boost.org/libs/utility/value_init.htm" target="_top">value_initialized</a>< <a href="./deref.html" class="identifier">deref</a><i<sub>n</sub>>::type > x<sub>n</sub>; |
| f(boost::get(x<sub>n</sub>)); |
| typedef <a href="./next.html" class="identifier">next</a><i<sub>n</sub>>::type last; |
| </pre> |
| <p class="last">where <tt class="literal"><span class="pre">n</span> <span class="pre">==</span> <span class="pre"><a href="./size.html" class="identifier">size</a><s>::value</span></tt> and <tt class="literal"><span class="pre">last</span></tt> is identical to |
| <tt class="literal"><span class="pre"><a href="./end.html" class="identifier">end</a><s>::type</span></tt>; no effect if <tt class="literal"><span class="pre"><a href="./empty.html" class="identifier">empty</a><s>::value</span> <span class="pre">==</span> <span class="pre">true</span></tt>.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| <pre class="literal-block"> |
| <a href="./for-each.html" class="identifier">for_each</a><s,op>( f ); |
| </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"><tt class="literal"><span class="pre">void</span></tt></p> |
| </td> |
| </tr> |
| <tr class="field"><th class="field-name">Postcondition:</th><td class="field-body"><p class="first">Equivalent to</p> |
| <pre class="last literal-block"> |
| <a href="./for-each.html" class="identifier">for_each</a>< tranform_view<s,op> >( f ); |
| </pre> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id817"> |
| <h3><a class="subsection-title" href="#complexity" name="complexity">Complexity</a></h3> |
| <p>Linear. Exactly <tt class="literal"><span class="pre"><a href="./size.html" class="identifier">size</a><s>::value</span></tt> applications of <tt class="literal"><span class="pre">op</span></tt> and <tt class="literal"><span class="pre">f</span></tt>.</p> |
| </div> |
| <div class="section" id="id818"> |
| <h3><a class="subsection-title" href="#example" name="example">Example</a></h3> |
| <pre class="literal-block"> |
| struct value_printer |
| { |
| template< typename U > void operator()(U x) |
| { |
| std::cout << x << 'n'; |
| } |
| }; |
| |
| int main() |
| { |
| <a href="./for-each.html" class="identifier">for_each</a>< <a href="./range-c.html" class="identifier">range_c</a><int,0,10> >( value_printer() ); |
| } |
| </pre> |
| </div> |
| <div class="section" id="id819"> |
| <h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> |
| <p><a class="reference internal" href="./runtime-algorithms.html">Runtime Algorithms</a>, <a class="reference internal" href="./views.html">Views</a>, <a class="reference internal" href="./transform-view.html">transform_view</a></p> |
| </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="./runtime-algorithms.html" class="navigation-link">Prev</a> <a href="./metafunctions.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group">Back Along</span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./runtime-algorithms.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> |
