1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Unicode Iterators</title> 5<link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../index.html" title="Boost.Regex 5.1.4"> 8<link rel="up" href="../internals.html" title="Internal Details"> 9<link rel="prev" href="../internals.html" title="Internal Details"> 10<link rel="next" href="../../background.html" title="Background Information"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td 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29<h5> 30<a name="boost_regex.ref.internals.uni_iter.h0"></a> 31 <span class="phrase"><a name="boost_regex.ref.internals.uni_iter.synopsis"></a></span><a class="link" href="uni_iter.html#boost_regex.ref.internals.uni_iter.synopsis">Synopsis</a> 32 </h5> 33<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">regex</span><span class="special">/</span><span class="identifier">pending</span><span class="special">/</span><span class="identifier">unicode_iterator</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></pre> 34<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U16Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint16_t</span><span class="special">></span> 35<span class="keyword">class</span> <span class="identifier">u32_to_u16_iterator</span><span class="special">;</span> 36 37<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">></span> 38<span class="keyword">class</span> <span class="identifier">u16_to_u32_iterator</span><span class="special">;</span> 39 40<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U8Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint8_t</span><span class="special">></span> 41<span class="keyword">class</span> <span class="identifier">u32_to_u8_iterator</span><span class="special">;</span> 42 43<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">></span> 44<span class="keyword">class</span> <span class="identifier">u8_to_u32_iterator</span><span class="special">;</span> 45 46<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">></span> 47<span class="keyword">class</span> <span class="identifier">utf16_output_iterator</span><span class="special">;</span> 48 49<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">></span> 50<span class="keyword">class</span> <span class="identifier">utf8_output_iterator</span><span class="special">;</span> 51</pre> 52<h5> 53<a name="boost_regex.ref.internals.uni_iter.h1"></a> 54 <span class="phrase"><a name="boost_regex.ref.internals.uni_iter.description"></a></span><a class="link" href="uni_iter.html#boost_regex.ref.internals.uni_iter.description">Description</a> 55 </h5> 56<p> 57 This header contains a selection of iterator adaptors that make a sequence 58 of characters in one encoding "look like" a read-only sequence 59 of characters in another encoding. 60 </p> 61<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U16Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint16_t</span><span class="special">></span> 62<span class="keyword">class</span> <span class="identifier">u32_to_u16_iterator</span> 63<span class="special">{</span> 64 <span class="identifier">u32_to_u16_iterator</span><span class="special">();</span> 65 <span class="identifier">u32_to_u16_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span> 66 67 <span class="comment">// Other standard BidirectionalIterator members here...</span> 68<span class="special">};</span> 69</pre> 70<p> 71 A Bidirectional iterator adapter that makes an underlying sequence of UTF32 72 characters look like a (read-only) sequence of UTF16 characters. The UTF16 73 characters are encoded in the platforms native byte order. 74 </p> 75<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">></span> 76<span class="keyword">class</span> <span class="identifier">u16_to_u32_iterator</span> 77<span class="special">{</span> 78 <span class="identifier">u16_to_u32_iterator</span><span class="special">();</span> 79 <span class="identifier">u16_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span> 80 <span class="identifier">u16_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">start_range</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">end_range</span><span class="special">);</span> 81 82 <span class="comment">// Other standard BidirectionalIterator members here...</span> 83<span class="special">};</span> 84</pre> 85<p> 86 A Bidirectional iterator adapter that makes an underlying sequence of UTF16 87 characters (in the platforms native byte order) look like a (read-only) 88 sequence of UTF32 characters. 89 </p> 90<p> 91 The three-arg constructor of this class takes the start and end of the 92 underlying sequence as well as the position to start iteration from. This 93 constructor validates that the underlying sequence has validly encoded 94 endpoints: this prevents accidentally incrementing/decrementing past the 95 end of the underlying sequence as a result of invalid UTF16 code sequences 96 at the endpoints of the underlying range. 97 </p> 98<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U8Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint8_t</span><span class="special">></span> 99<span class="keyword">class</span> <span class="identifier">u32_to_u8_iterator</span> 100<span class="special">{</span> 101 <span class="identifier">u32_to_u8_iterator</span><span class="special">();</span> 102 <span class="identifier">u32_to_u8_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span> 103 104 <span class="comment">// Other standard BidirectionalIterator members here...</span> 105<span class="special">};</span> 106</pre> 107<p> 108 A Bidirectional iterator adapter that makes an underlying sequence of UTF32 109 characters look like a (read-only) sequence of UTF8 characters. 110 </p> 111<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">U32Type</span> <span class="special">=</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">uint32_t</span><span class="special">></span> 112<span class="keyword">class</span> <span class="identifier">u8_to_u32_iterator</span> 113<span class="special">{</span> 114 <span class="identifier">u8_to_u32_iterator</span><span class="special">();</span> 115 <span class="identifier">u8_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">);</span> 116 <span class="identifier">u8_to_u32_iterator</span><span class="special">(</span><span class="identifier">BaseIterator</span> <span class="identifier">start_position</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">start_range</span><span class="special">,</span> <span class="identifier">BaseIterator</span> <span class="identifier">end_range</span><span class="special">);</span> 117 118 <span class="comment">// Other standard BidirectionalIterator members here...</span> 119<span class="special">};</span> 120</pre> 121<p> 122 A Bidirectional iterator adapter that makes an underlying sequence of UTF8 123 characters look like a (read-only) sequence of UTF32 characters. 124 </p> 125<p> 126 The three-arg constructor of this class takes the start and end of the 127 underlying sequence as well as the position to start iteration from. This 128 constructor validates that the underlying sequence has validly encoded 129 endpoints: this prevents accidentally incrementing/decrementing past the 130 end of the underlying sequence as a result of invalid UTF8 code sequences 131 at the endpoints of the underlying range. 132 </p> 133<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">></span> 134<span class="keyword">class</span> <span class="identifier">utf16_output_iterator</span> 135<span class="special">{</span> 136 <span class="identifier">utf16_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">BaseIterator</span><span class="special">&</span> <span class="identifier">b</span><span class="special">);</span> 137 <span class="identifier">utf16_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">utf16_output_iterator</span><span class="special">&</span> <span class="identifier">that</span><span class="special">);</span> 138 <span class="identifier">utf16_output_iterator</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">utf16_output_iterator</span><span class="special">&</span> <span class="identifier">that</span><span class="special">);</span> 139 140 <span class="comment">// Other standard OutputIterator members here...</span> 141<span class="special">};</span> 142</pre> 143<p> 144 Simple OutputIterator adapter - accepts UTF32 values as input, and forwards 145 them to <span class="emphasis"><em>BaseIterator b</em></span> as UTF16. Both UTF32 and UTF16 146 values are in native byte order. 147 </p> 148<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">BaseIterator</span><span class="special">></span> 149<span class="keyword">class</span> <span class="identifier">utf8_output_iterator</span> 150<span class="special">{</span> 151 <span class="identifier">utf8_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">BaseIterator</span><span class="special">&</span> <span class="identifier">b</span><span class="special">);</span> 152 <span class="identifier">utf8_output_iterator</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">utf8_output_iterator</span><span class="special">&</span> <span class="identifier">that</span><span class="special">);</span> 153 <span class="identifier">utf8_output_iterator</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">utf8_output_iterator</span><span class="special">&</span> <span class="identifier">that</span><span class="special">);</span> 154 155 <span class="comment">// Other standard OutputIterator members here...</span> 156<span class="special">};</span> 157</pre> 158<p> 159 Simple OutputIterator adapter - accepts UTF32 values as input, and forwards 160 them to <span class="emphasis"><em>BaseIterator b</em></span> as UTF8. The UTF32 input values 161 must be in native byte order. 162 </p> 163</div> 164<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 165<td align="left"></td> 166<td align="right"><div class="copyright-footer">Copyright © 1998-2013 John Maddock<p> 167 Distributed under the Boost Software License, Version 1.0. (See accompanying 168 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>) 169 </p> 170</div></td> 171</tr></table> 172<hr> 173<div class="spirit-nav"> 174<a accesskey="p" href="../internals.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../internals.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="../../background.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 175</div> 176</body> 177</html> 178
