1<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 2<html xmlns="http://www.w3.org/1999/xhtml"> 3<head> 4<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/> 5<meta http-equiv="X-UA-Compatible" content="IE=9"/> 6<meta name="generator" content="Doxygen 1.8.6"/> 7<title>Boost.Locale: Collation</title> 8<link href="tabs.css" rel="stylesheet" type="text/css"/> 9<script type="text/javascript" src="jquery.js"></script> 10<script type="text/javascript" src="dynsections.js"></script> 11<link href="navtree.css" rel="stylesheet" type="text/css"/> 12<script type="text/javascript" src="resize.js"></script> 13<script type="text/javascript" src="navtree.js"></script> 14<script type="text/javascript"> 15 $(document).ready(initResizable); 16 $(window).load(resizeHeight); 17</script> 18<link href="doxygen.css" rel="stylesheet" type="text/css" /> 19</head> 20<body> 21<div id="top"><!-- do not remove this div, it is closed by doxygen! --> 22<div id="titlearea"> 23<table cellspacing="0" cellpadding="0"> 24 <tbody> 25 <tr style="height: 56px;"> 26 <td id="projectlogo"><img alt="Logo" src="boost-small.png"/></td> 27 <td style="padding-left: 0.5em;"> 28 <div id="projectname">Boost.Locale 29 </div> 30 </td> 31 </tr> 32 </tbody> 33</table> 34</div> 35<!-- end header part --> 36<!-- Generated by Doxygen 1.8.6 --> 37 <div id="navrow1" class="tabs"> 38 <ul class="tablist"> 39 <li><a href="index.html"><span>Main Page</span></a></li> 40 <li class="current"><a href="pages.html"><span>Related Pages</span></a></li> 41 <li><a href="modules.html"><span>Modules</span></a></li> 42 <li><a href="namespaces.html"><span>Namespaces</span></a></li> 43 <li><a href="annotated.html"><span>Classes</span></a></li> 44 <li><a href="files.html"><span>Files</span></a></li> 45 <li><a href="examples.html"><span>Examples</span></a></li> 46 </ul> 47 </div> 48</div><!-- top --> 49<div id="side-nav" class="ui-resizable side-nav-resizable"> 50 <div id="nav-tree"> 51 <div id="nav-tree-contents"> 52 <div id="nav-sync" class="sync"></div> 53 </div> 54 </div> 55 <div id="splitbar" style="-moz-user-select:none;" 56 class="ui-resizable-handle"> 57 </div> 58</div> 59<script type="text/javascript"> 60$(document).ready(function(){initNavTree('collation.html','');}); 61</script> 62<div id="doc-content"> 63<div class="header"> 64 <div class="headertitle"> 65<div class="title">Collation </div> </div> 66</div><!--header--> 67<div class="contents"> 68<div class="textblock"><p>Boost.Locale provides a <a class="el" href="classboost_1_1locale_1_1collator.html">collator</a> class, derived from <code>std::collate</code>, that adds support for primary, secondary, tertiary, quaternary and identical comparison levels. They can be approximately defined as:</p> 69<ol type="1"> 70<li>Primary – ignore accents and character case, comparing base letters only. For example "facade" and "Façade" are the same.</li> 71<li>Secondary – ignore character case but consider accents. "facade" and "façade" are different but "Façade" and "façade" are the same.</li> 72<li>Tertiary – consider both case and accents: "Façade" and "façade" are different. Ignore punctuation.</li> 73<li>Quaternary – consider all case, accents, and punctuation. The words must be identical in terms of Unicode representation.</li> 74<li>Identical – as quaternary, but compare code points as well.</li> 75</ol> 76<p>There are two ways of using the <a class="el" href="classboost_1_1locale_1_1collator.html">collator</a> facet: directly, by calling its member functions <a class="el" href="classboost_1_1locale_1_1collator.html#ab90dc7bb909a71d3cd9a5e8d7b2eb80e">compare</a>, <a class="el" href="classboost_1_1locale_1_1collator.html#a8dc6443fb193616332ca50f207a9b189">transform</a> and <a class="el" href="classboost_1_1locale_1_1collator.html#a89752e2023643f972b6cc8024340d5d4">hash</a>, or indirectly by using the <a class="el" href="structboost_1_1locale_1_1comparator.html">comparator</a> template class in STL algorithms.</p> 77<p>For example:</p> 78<div class="fragment"><div class="line">wstring a=L<span class="stringliteral">"Façade"</span>, b=L<span class="stringliteral">"facade"</span>;</div> 79<div class="line"><span class="keywordtype">bool</span> eq = 0 == use_facet<collator<wchar_t> >(loc).compare(collator_base::secondary,a,b);</div> 80<div class="line">wcout << a <<L<span class="stringliteral">" and "</span><<b<<L<span class="stringliteral">" are "</span> << (eq ? L<span class="stringliteral">"identical"</span> : L<span class="stringliteral">"different"</span>)<<endl;</div> 81</div><!-- fragment --><p><code>std::locale</code> is designed to be useful as a comparison class in STL collections and algorithms. To get similar functionality with comparison levels, you must use the comparator class.</p> 82<div class="fragment"><div class="line">std::map<std::string,std::string,comparator<char,collator_base::secondary> > strings;</div> 83<div class="line"><span class="comment">// Now strings uses the default system locale for string comparison</span></div> 84</div><!-- fragment --><p>You can also set a specific locale or level when creating and using the <a class="el" href="structboost_1_1locale_1_1comparator.html">comparator</a> class:</p> 85<div class="fragment"><div class="line">comparator<char> comp(some_locale,some_level);</div> 86<div class="line">std::map<std::string,std::string,comparator<char> > strings(comp);</div> 87</div><!-- fragment --> </div></div><!-- contents --> 88</div><!-- doc-content --> 89 90 <li class="footer"> 91© Copyright 2009-2012 Artyom Beilis, Distributed under the <a href="http://www.boost.org/LICENSE_1_0.txt">Boost Software License</a>, Version 1.0. 92 </li> 93 </ul> 94 </div> 95</body> 96</html> 97
