<?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"> <!-- Copyright Aleksey Gurtovoy 2006. Distributed under the Boost --> <!-- Software License, Version 1.0. (See accompanying --> <!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) --> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <meta name="generator" content="Docutils 0.3.6: http://docutils.sourceforge.net/" /> <title>THE BOOST MPL LIBRARY: Tag Dispatching Protocol</title> <link rel="stylesheet" href="../style.css" type="text/css" /> </head> <body class="docframe"> <table class="header"><tr class="header"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./iterator-protocol.html" class="navigation-link">Prev</a> <a href="./numeric-metafunction.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./iterator-protocol.html" class="navigation-link">Back</a> <a href="./numeric-metafunction.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./changes-in-boost-1-32-0.html" class="navigation-link">Up</a> <a href="../index.html" class="navigation-link">Home</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./tutorial_toc.html" class="navigation-link">Full TOC</a></span></td> <td class="header-group page-location"><a href="../index.html" class="navigation-link">Front Page</a> / <a href="./changelog-history.html" class="navigation-link">Changelog & History</a> / <a href="./changes-in-boost-1-32-0.html" class="navigation-link">Changes in Boost 1.32.0 Release</a> / <a href="./tag-dispatching-protocol.html" class="navigation-link">Tag Dispatching Protocol</a></td> </tr></table><div class="header-separator"></div> <div class="section" id="tag-dispatching-protocol"> <h1><a class="toc-backref" href="./changes-in-boost-1-32-0.html#id66" name="tag-dispatching-protocol">Tag Dispatching Protocol</a></h1> <p>The mechanism used to select algorithm implementations based on sequence family has been changed to use metafunction classes:</p> <table border="1" class="table"> <colgroup> <col width="53%" /> <col width="47%" /> </colgroup> <thead valign="bottom"> <tr><th>Before</th> <th>Now</th> </tr> </thead> <tbody valign="top"> <tr><td><em>name</em><tt class="literal"><span class="pre">_traits<Tag>::algorithm<...>::type</span></tt></td> <td><em>name</em><tt class="literal"><span class="pre">_impl<Tag>::apply<...>::type</span></tt></td> </tr> </tbody> </table> <p>If your code implemented a custom sequence, it needs to be adjusted according to the above table; for example:</p> <table border="1" class="table"> <colgroup> <col width="50%" /> <col width="50%" /> </colgroup> <thead valign="bottom"> <tr><th>Before</th> <th>Now</th> </tr> </thead> <tbody valign="top"> <tr><td><pre class="first last literal-block"> template<> struct begin_traits<my_tag> { template< typename S > struct algorithm { typedef ... type; }; }; </pre> </td> <td><pre class="first last literal-block"> template<> struct begin_<strong>impl</strong><my_tag> { template< typename S > struct <strong>apply</strong> { typedef ... type; }; }; </pre> </td> </tr> </tbody> </table> </div> <div class="footer-separator"></div> <table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./iterator-protocol.html" class="navigation-link">Prev</a> <a href="./numeric-metafunction.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./iterator-protocol.html" class="navigation-link">Back</a> <a href="./numeric-metafunction.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./changes-in-boost-1-32-0.html" class="navigation-link">Up</a> <a href="../index.html" class="navigation-link">Home</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./tutorial_toc.html" class="navigation-link">Full TOC</a></span></td> </tr></table></body> </html>