devn00b
/
EQ2EMu


			
				
					
						
						
							1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586
							<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
<title>Unicode and Boost.Regex</title>
<link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="../index.html" title="Boost.Regex 5.1.4">
<link rel="up" href="../index.html" title="Boost.Regex 5.1.4">
<link rel="prev" href="intro.html" title="Introduction and Overview">
<link rel="next" href="captures.html" title="Understanding Marked Sub-Expressions and Captures">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table cellpadding="2" width="100%"><tr>
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../boost.png"></td>
<td align="center"><a href="../../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../../libs/libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
<td align="center"><a href="../../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="intro.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../index.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="captures.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>
</div>
<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_regex.unicode"></a><a class="link" href="unicode.html" title="Unicode and Boost.Regex">Unicode and Boost.Regex</a>
</h2></div></div></div>
<p>
      There are two ways to use Boost.Regex with Unicode strings:
    </p>
<h5>
<a name="boost_regex.unicode.h0"></a>
      <span class="phrase"><a name="boost_regex.unicode.rely_on_wchar_t"></a></span><a class="link" href="unicode.html#boost_regex.unicode.rely_on_wchar_t">Rely
      on wchar_t</a>
    </h5>
<p>
      If your platform's <code class="computeroutput"><span class="keyword">wchar_t</span></code> type
      can hold Unicode strings, and your platform's C/C++ runtime correctly handles
      wide character constants (when passed to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">iswspace</span></code>
      <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">iswlower</span></code> etc), then you can use <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">wregex</span></code>
      to process Unicode. However, there are several disadvantages to this approach:
    </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
          It's not portable: there's no guarantee on the width of <code class="computeroutput"><span class="keyword">wchar_t</span></code>,
          or even whether the runtime treats wide characters as Unicode at all, most
          Windows compilers do so, but many Unix systems do not.
        </li>
<li class="listitem">
          There's no support for Unicode-specific character classes: <code class="computeroutput"><span class="special">[[:</span><span class="identifier">Nd</span><span class="special">:]]</span></code>, <code class="computeroutput"><span class="special">[[:</span><span class="identifier">Po</span><span class="special">:]]</span></code>
          etc.
        </li>
<li class="listitem">
          You can only search strings that are encoded as sequences of wide characters,
          it is not possible to search UTF-8, or even UTF-16 on many platforms.
        </li>
</ul></div>
<h5>
<a name="boost_regex.unicode.h1"></a>
      <span class="phrase"><a name="boost_regex.unicode.use_a_unicode_aware_regular_expr"></a></span><a class="link" href="unicode.html#boost_regex.unicode.use_a_unicode_aware_regular_expr">Use
      a Unicode Aware Regular Expression Type.</a>
    </h5>
<p>
      If you have the <a href="http://www.ibm.com/software/globalization/icu/" target="_top">ICU
      library</a>, then Boost.Regex can be <a class="link" href="install.html#boost_regex.install.building_with_unicode_and_icu_su">configured
      to make use of it</a>, and provide a distinct regular expression type (boost::u32regex),
      that supports both Unicode specific character properties, and the searching
      of text that is encoded in either UTF-8, UTF-16, or UTF-32. See: <a class="link" href="ref/non_std_strings/icu.html" title="Working With Unicode and ICU String Types">ICU
      string class support</a>.
    </p>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright &#169; 1998-2013 John Maddock<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="intro.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../index.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="captures.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>
</div>
</body>
</html>