<?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: transform</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="./copy-if.html" class="navigation-link">Prev</a> <a href="./replace.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./copy-if.html" class="navigation-link">Back</a> <a href="./replace.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./transformation-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="./transformation-algorithms.html" class="navigation-link">Transformation Algorithms</a> / <a href="./transform.html" class="navigation-link">transform</a></td> </tr></table><div class="header-separator"></div> <div class="section" id="transform"> <h1><a class="toc-backref" href="./transformation-algorithms.html#id1488">transform</a></h1> <div class="section" id="id633"> <h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> <pre class="literal-block"> template< typename Sequence , typename Op , typename In = <em>unspecified</em> > struct <a href="./transform.html" class="identifier">transform</a> { typedef <em>unspecified</em> type; }; template< typename Seq1 , typename Seq2 , typename BinaryOp , typename In = <em>unspecified</em> > struct <a href="./transform.html" class="identifier">transform</a> { typedef <em>unspecified</em> type; }; </pre> </div> <div class="section" id="id634"> <h3><a class="subsection-title" href="#description" name="description">Description</a></h3> <p><tt class="literal"><span class="pre"><a href="./transform.html" class="identifier">transform</a></span></tt> is an <a class="reference internal" href="./terminology.html#overloaded-name">overloaded name</a>:</p> <ul class="simple"> <li><tt class="literal"><span class="pre"><a href="./transform.html" class="identifier">transform</a><Sequence,Op></span></tt> returns a transformed copy of the original sequence produced by applying an unary transformation <tt class="literal"><span class="pre">Op</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="./transform.html" class="identifier">transform</a><Seq1,Seq2,BinaryOp></span></tt> returns a new sequence produced by applying a binary transformation <tt class="literal"><span class="pre">BinaryOp</span></tt> to a pair of elements (e<sub>1</sub>, e2<sub>1</sub>) from the corresponding [<tt class="literal"><span class="pre"><a href="./begin.html" class="identifier">begin</a><Seq1>::type</span></tt>, <tt class="literal"><span class="pre"><a href="./end.html" class="identifier">end</a><Seq1>::type</span></tt>) and [<tt class="literal"><span class="pre"><a href="./begin.html" class="identifier">begin</a><Seq2>::type</span></tt>, <tt class="literal"><span class="pre"><a href="./end.html" class="identifier">end</a><Seq2>::type</span></tt>) ranges.</li> </ul> <p>[<em>Note:</em> This wording applies to a no-inserter version(s) of the algorithm. See the <cite>Expression semantics</cite> subsection for a precise specification of the algorithm's details in all cases — <em>end note</em>]</p> </div> <div class="section" id="id635"> <h3><a class="subsection-title" href="#header" name="header">Header</a></h3> <pre class="literal-block"> #include <<a href="../../../../boost/mpl/transform.hpp" class="header">boost/mpl/transform.hpp</a>> </pre> </div> <div class="section" id="id636"> <h3><a class="subsection-title" href="#model-of" name="model-of">Model of</a></h3> <p><a class="reference internal" href="./reversible-algorithm.html">Reversible Algorithm</a></p> </div> <div class="section" id="id637"> <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>, <tt class="literal"><span class="pre">Seq1</span></tt>, <tt class="literal"><span class="pre">Seq2</span></tt></td> <td><a class="reference internal" href="./forward-sequence.html">Forward Sequence</a></td> <td>Sequences to transform.</td> </tr> <tr><td><tt class="literal"><span class="pre">Op</span></tt>, <tt class="literal"><span class="pre">BinaryOp</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">In</span></tt></td> <td><a class="reference internal" href="./inserter.html">Inserter</a></td> <td>An inserter.</td> </tr> </tbody> </table> </div> <div class="section" id="id638"> <h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> <p>The semantics of an expression are defined only where they differ from, or are not defined in <a class="reference internal" href="./reversible-algorithm.html">Reversible Algorithm</a>.</p> <p>For any <a class="reference internal" href="./forward-sequence.html">Forward Sequence</a>s <tt class="literal"><span class="pre">s</span></tt>, <tt class="literal"><span class="pre">s1</span></tt> and <tt class="literal"><span class="pre">s2</span></tt>, <a class="reference internal" href="./lambda-expression.html">Lambda Expression</a>s <tt class="literal"><span class="pre">op</span></tt> and <tt class="literal"><span class="pre">op2</span></tt>, and an <a class="reference internal" href="./inserter.html">Inserter</a> <tt class="literal"><span class="pre">in</span></tt>:</p> <pre class="literal-block"> typedef <a href="./transform.html" class="identifier">transform</a><s,op,in>::type r; </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">A type.</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"> typedef <a href="./lambda.html" class="identifier">lambda</a><op>::type f; typedef <a href="./lambda.html" class="identifier">lambda</a><in::operation>::type in_op; typedef <a href="./fold.html" class="identifier">fold</a>< s , in::state , <a href="./bind.html" class="identifier">bind</a>< in_op, <a href="./placeholders.html" class="identifier">_1</a>, <a href="./bind.html" class="identifier">bind</a><f, <a href="./placeholders.html" class="identifier">_2</a>> > >::type r; </pre> </td> </tr> </tbody> </table> <pre class="literal-block"> typedef <a href="./transform.html" class="identifier">transform</a><s1,s2,op,in>::type r; </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">A type.</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"> typedef <a href="./lambda.html" class="identifier">lambda</a><op2>::type f; typedef <a href="./lambda.html" class="identifier">lambda</a><in::operation>::type in_op; typedef <a href="./fold.html" class="identifier">fold</a>< pair_view<s1,s2> , in::state , <a href="./bind.html" class="identifier">bind</a>< in_op , <a href="./placeholders.html" class="identifier">_1</a> , <a href="./bind.html" class="identifier">bind</a><f, <a href="./bind.html" class="identifier">bind</a><first<>,<a href="./placeholders.html" class="identifier">_2</a>>, <a href="./bind.html" class="identifier">bind</a><second<>,<a href="./placeholders.html" class="identifier">_2</a>> > > >::type r; </pre> </td> </tr> </tbody> </table> </div> <div class="section" id="id639"> <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> / <tt class="literal"><span class="pre"><a href="./size.html" class="identifier">size</a><s1>::value</span></tt> applications of <tt class="literal"><span class="pre">op</span></tt> / <tt class="literal"><span class="pre">op2</span></tt> and <tt class="literal"><span class="pre">in::operation</span></tt>.</p> </div> <div class="section" id="id640"> <h3><a class="subsection-title" href="#example" name="example">Example</a></h3> <pre class="literal-block"> typedef <a href="./vector.html" class="identifier">vector</a><char,short,int,long,float,double> types; typedef <a href="./vector.html" class="identifier">vector</a><char*,short*,int*,long*,float*,double*> pointers; typedef <a href="./transform.html" class="identifier">transform</a>< types,boost::add_pointer<<a href="./placeholders.html" class="identifier">_1</a>> >::type result; <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( <a href="./equal.html" class="identifier">equal</a><result,pointers> )); </pre> </div> <div class="section" id="id641"> <h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> <p><a class="reference internal" href="./transformation-algorithms.html">Transformation Algorithms</a>, <a class="reference internal" href="./reversible-algorithm.html">Reversible Algorithm</a>, <a class="reference internal" href="./reverse-transform.html">reverse_transform</a>, <a class="reference internal" href="./copy.html">copy</a>, <a class="reference internal" href="./replace-if.html">replace_if</a></p> <!-- Algorithms/Transformation Algorithms//replace |40 --> </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="./copy-if.html" class="navigation-link">Prev</a> <a href="./replace.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./copy-if.html" class="navigation-link">Back</a> <a href="./replace.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./transformation-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>