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Boost-Commit : |
Subject: [Boost-commit] svn:boost r82489 - in trunk/libs/utility/doc: . html
From: marshall_at_[hidden]
Date: 2013-01-14 11:25:57
Author: marshall
Date: 2013-01-14 11:25:56 EST (Mon, 14 Jan 2013)
New Revision: 82489
URL: http://svn.boost.org/trac/boost/changeset/82489
Log:
Updated the string_ref docs with a reference section; committed the generated HTML
Added:
trunk/libs/utility/doc/html/string_ref.html (contents, props changed)
Text files modified:
trunk/libs/utility/doc/Jamfile.v2 | 6 +-
trunk/libs/utility/doc/string_ref.qbk | 93 ++++++++++++++++++++++++++++++++++-----
2 files changed, 83 insertions(+), 16 deletions(-)
Modified: trunk/libs/utility/doc/Jamfile.v2
==============================================================================
--- trunk/libs/utility/doc/Jamfile.v2 (original)
+++ trunk/libs/utility/doc/Jamfile.v2 2013-01-14 11:25:56 EST (Mon, 14 Jan 2013)
@@ -43,7 +43,7 @@
path-constant boost-images : ../../../doc/src/images ;
xml declval : declval.qbk ;
-boostbook standalone
+boostbook standalone_declval
:
declval
:
@@ -63,7 +63,7 @@
;
xml string_ref : string_ref.qbk ;
-boostbook standalone
+boostbook standalone_string_ref
:
string_ref
:
@@ -79,5 +79,5 @@
<xsl:param>toc.max.depth=1
# How far down we go with TOC's
<xsl:param>generate.section.toc.level=1
-
+
;
Added: trunk/libs/utility/doc/html/string_ref.html
==============================================================================
--- (empty file)
+++ trunk/libs/utility/doc/html/string_ref.html 2013-01-14 11:25:56 EST (Mon, 14 Jan 2013)
@@ -0,0 +1,280 @@
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<title>String_Ref</title>
+<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css">
+<meta name="generator" content="DocBook XSL Stylesheets V1.75.2">
+<link rel="home" href="string_ref.html" title="String_Ref">
+</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">Home</td>
+<td align="center">Libraries</td>
+<td align="center">People</td>
+<td align="center">FAQ</td>
+<td align="center">More</td>
+</tr></table>
+<hr>
+<div class="spirit-nav"></div>
+<div class="article">
+<div class="titlepage">
+<div>
+<div><h2 class="title">
+<a name="string_ref"></a>String_Ref</h2></div>
+<div><div class="authorgroup"><div class="author"><h3 class="author">
+<span class="firstname">Marshall</span> <span class="surname">Clow</span>
+</h3></div></div></div>
+<div><p class="copyright">Copyright © 2012 Marshall Clow</p></div>
+<div><div class="legalnotice">
+<a name="string_ref.legal"></a><p>
+ 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)
+ </p>
+</div></div>
+</div>
+<hr>
+</div>
+<div class="toc">
+<p><b>Table of Contents</b></p>
+<dl>
+<dt><span class="section">Overview</span></dt>
+<dt><span class="section">Examples</span></dt>
+<dt><span class="section">Reference </span></dt>
+<dt><span class="section">History</span></dt>
+</dl>
+</div>
+<div class="section string_ref_overview">
+<div class="titlepage"><div><div><h2 class="title" style="clear: both">
+<a name="string_ref.overview"></a><a class="link" href="string_ref.html#string_ref.overview" title="Overview">Overview</a>
+</h2></div></div></div>
+<p>
+ Boost.StringRef is an implementation of Jeffrey Yaskin's <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3442.html" target="_top">N3442:
+ string_ref: a non-owning reference to a string</a>.
+ </p>
+<p>
+ When you are parsing/processing strings from some external source, frequently
+ you want to pass a piece of text to a procedure for specialized processing.
+ The canonical way to do this is as a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>,
+ but that has certain drawbacks:
+ </p>
+<p>
+ 1) If you are processing a buffer of text (say a HTTP response or the contents
+ of a file), then you have to create the string from the text you want to pass,
+ which involves memory allocation and copying of data.
+ </p>
+<p>
+ 2) if a routine receives a constant <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>
+ and wants to pass a portion of that string to another routine, then it must
+ create a new string of that substring.
+ </p>
+<p>
+ 3) A routine receives a constant <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>
+ and wants to return a portion of the string, then it must create a new string
+ to return.
+ </p>
+<p>
+ <code class="computeroutput"><span class="identifier">string_ref</span></code> is designed to solve
+ these efficiency problems. A <code class="computeroutput"><span class="identifier">string_ref</span></code>
+ is a read-only reference to a contiguous sequence of characters, and provides
+ much of the functionality of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>.
+ A <code class="computeroutput"><span class="identifier">string_ref</span></code> is cheap to create,
+ copy and pass by value, because it does not actually own the storage that it
+ points to.
+ </p>
+<p>
+ A <code class="computeroutput"><span class="identifier">string_ref</span></code> is implemented
+ as a small struct that contains a pointer to the start of the character data
+ and a count. A <code class="computeroutput"><span class="identifier">string_ref</span></code> is
+ cheap to create and cheap to copy.
+ </p>
+<p>
+ <code class="computeroutput"><span class="identifier">string_ref</span></code> acts as a container;
+ it includes all the methods that you would expect in a container, including
+ iteration support, <code class="computeroutput"><span class="keyword">operator</span> <span class="special">[]</span></code>,
+ <code class="computeroutput"><span class="identifier">at</span></code> and <code class="computeroutput"><span class="identifier">size</span></code>.
+ It can be used with any of the iterator-based algorithms in the STL - as long
+ as you don't need to change the underlying data (<code class="computeroutput"><span class="identifier">sort</span></code>
+ and <code class="computeroutput"><span class="identifier">remove</span></code>, for example, will
+ not work)
+ </p>
+<p>
+ Besides generic container functionality, <code class="computeroutput"><span class="identifier">string_ref</span></code>
+ provides a subset of the interface of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>.
+ This makes it easy to replace parameters of type <code class="computeroutput"><span class="keyword">const</span>
+ <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">&</span></code>
+ with <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">string_ref</span></code>. Like <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>,
+ <code class="computeroutput"><span class="identifier">string_ref</span></code> has a static member
+ variable named <code class="computeroutput"><span class="identifier">npos</span></code> to denote
+ the result of failed searches, and to mean "the end".
+ </p>
+<p>
+ Because a <code class="computeroutput"><span class="identifier">string_ref</span></code> does not
+ own the data that it "points to", it introduces lifetime issues into
+ code that uses it. The programmer must ensure that the data that a <code class="computeroutput"><span class="identifier">string_ref</span></code> refers to exists as long as the
+ <code class="computeroutput"><span class="identifier">string_ref</span></code> does.
+ </p>
+</div>
+<div class="section string_ref_examples">
+<div class="titlepage"><div><div><h2 class="title" style="clear: both">
+<a name="string_ref.examples"></a><a class="link" href="string_ref.html#string_ref.examples" title="Examples">Examples</a>
+</h2></div></div></div>
+<p>
+ Integrating <code class="computeroutput"><span class="identifier">string_ref</span></code> into
+ your code is fairly simple. Wherever you pass a <code class="computeroutput"><span class="keyword">const</span>
+ <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">&</span></code>
+ or <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code> as a parameter, that's a candidate
+ for passing a <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">string_ref</span></code>.
+ </p>
+<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">extract_part</span> <span class="special">(</span> <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">&</span><span class="identifier">bar</span> <span class="special">)</span> <span class="special">{</span>
+ <span class="keyword">return</span> <span class="identifier">bar</span><span class="special">.</span><span class="identifier">substr</span> <span class="special">(</span> <span class="number">2</span><span class="special">,</span> <span class="number">3</span> <span class="special">);</span>
+ <span class="special">}</span>
+
+<span class="keyword">if</span> <span class="special">(</span> <span class="identifier">extract_part</span> <span class="special">(</span> <span class="string">"ABCDEFG"</span> <span class="special">).</span><span class="identifier">front</span><span class="special">()</span> <span class="special">==</span> <span class="string">"C"</span> <span class="special">)</span> <span class="special">{</span> <span class="comment">/* do something */</span> <span class="special">}</span>
+</pre>
+<p>
+ Let's figure out what happens in this (contrived) example.
+ </p>
+<p>
+ First, a temporary string is created from the string literal <code class="computeroutput"><span class="string">"ABCDEFG"</span></code>, and it is passed (by reference)
+ to the routine <code class="computeroutput"><span class="identifier">extract_part</span></code>.
+ Then a second string is created in the call <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">substr</span></code>
+ and returned to <code class="computeroutput"><span class="identifier">extract_part</span></code>
+ (this copy may be elided by RVO). Then <code class="computeroutput"><span class="identifier">extract_part</span></code>
+ returns that string back to the caller (again this copy may be elided). The
+ first temporary string is deallocated, and <code class="computeroutput"><span class="identifier">front</span></code>
+ is called on the second string, and then it is deallocated as well.
+ </p>
+<p>
+ Two <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>s are created, and two copy operations.
+ That's (potentially) four memory allocations and deallocations, and the associated
+ copying of data.
+ </p>
+<p>
+ Now let's look at the same code with <code class="computeroutput"><span class="identifier">string_ref</span></code>:
+ </p>
+<pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">string_ref</span> <span class="identifier">extract_part</span> <span class="special">(</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">string_ref</span> <span class="identifier">bar</span> <span class="special">)</span> <span class="special">{</span>
+ <span class="keyword">return</span> <span class="identifier">bar</span><span class="special">.</span><span class="identifier">substr</span> <span class="special">(</span> <span class="number">2</span><span class="special">,</span> <span class="number">3</span> <span class="special">);</span>
+ <span class="special">}</span>
+
+<span class="keyword">if</span> <span class="special">(</span> <span class="identifier">extract_part</span> <span class="special">(</span> <span class="string">"ABCDEFG"</span> <span class="special">).</span><span class="identifier">front</span><span class="special">()</span> <span class="special">==</span> <span class="string">"C"</span> <span class="special">)</span> <span class="special">{</span> <span class="comment">/* do something */</span> <span class="special">}</span>
+</pre>
+<p>
+ No memory allocations. No copying of character data. No changes to the code
+ other than the types. There are two <code class="computeroutput"><span class="identifier">string_ref</span></code>s
+ created, and two <code class="computeroutput"><span class="identifier">string_ref</span></code>s
+ copied, but those are cheap operations.
+ </p>
+</div>
+<div class="section string_ref_reference">
+<div class="titlepage"><div><div><h2 class="title" style="clear: both">
+<a name="string_ref.reference"></a><a class="link" href="string_ref.html#string_ref.reference" title="Reference">Reference </a>
+</h2></div></div></div>
+<p>
+ The header file "string_ref.hpp" defines a template <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">basic_string_ref</span></code>,
+ and four specializations - for <code class="computeroutput"><span class="keyword">char</span></code>
+ / <code class="computeroutput"><span class="keyword">wchar_t</span></code> / <code class="computeroutput"><span class="identifier">char16_t</span></code>
+ / <code class="computeroutput"><span class="identifier">char32_t</span></code> .
+ </p>
+<p>
+ <code class="computeroutput"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">utility</span><span class="special">/</span><span class="identifier">string_ref</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span></code>
+ </p>
+<p>
+ Construction and copying:
+ </p>
+<pre class="programlisting"><span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">basic_string_ref</span> <span class="special">();</span> <span class="comment">// Constructs an empty string_ref</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">basic_string_ref</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">charT</span><span class="special">*</span> <span class="identifier">str</span><span class="special">);</span> <span class="comment">// Constructs from a NULL-terminated string</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">basic_string_ref</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">charT</span><span class="special">*</span> <span class="identifier">str</span><span class="special">,</span> <span class="identifier">size_type</span> <span class="identifier">len</span><span class="special">);</span> <span class="comment">// Constructs from a pointer, length pair</span>
+<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Allocator</span><span class="special">></span>
+<span class="identifier">basic_string_ref</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_string</span><span class="special"><</span><span class="identifier">charT</span><span class="special">,</span> <span class="identifier">traits</span><span class="special">,</span> <span class="identifier">Allocator</span><span class="special">>&</span> <span class="identifier">str</span><span class="special">);</span> <span class="comment">// Constructs from a std::string</span>
+<span class="identifier">basic_string_ref</span> <span class="special">(</span><span class="keyword">const</span> <span class="identifier">basic_string_ref</span> <span class="special">&</span><span class="identifier">rhs</span><span class="special">);</span>
+<span class="identifier">basic_string_ref</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">basic_string_ref</span> <span class="special">&</span><span class="identifier">rhs</span><span class="special">);</span>
+</pre>
+<p>
+ <code class="computeroutput"><span class="identifier">string_ref</span></code> does not define
+ a move constructor nor a move-assignment operator because copying a <code class="computeroutput"><span class="identifier">string_ref</span></code> is just a cheap as moving one.
+ </p>
+<p>
+ Basic container-like functions:
+ </p>
+<pre class="programlisting"><span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">size_type</span> <span class="identifier">size</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">size_type</span> <span class="identifier">length</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">size_type</span> <span class="identifier">max_size</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="keyword">bool</span> <span class="identifier">empty</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+
+<span class="comment">// All iterators are const_iterators</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">const_iterator</span> <span class="identifier">begin</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">const_iterator</span> <span class="identifier">cbegin</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">const_iterator</span> <span class="identifier">end</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">const_iterator</span> <span class="identifier">cend</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">const_reverse_iterator</span> <span class="identifier">rbegin</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">const_reverse_iterator</span> <span class="identifier">crbegin</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">const_reverse_iterator</span> <span class="identifier">rend</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">const_reverse_iterator</span> <span class="identifier">crend</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+</pre>
+<p>
+ Access to the individual elements (all of which are const):
+ </p>
+<pre class="programlisting"><span class="identifier">BOOST_CONSTEXPR</span> <span class="keyword">const</span> <span class="identifier">charT</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">[](</span><span class="identifier">size_type</span> <span class="identifier">pos</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="keyword">const</span> <span class="identifier">charT</span><span class="special">&</span> <span class="identifier">at</span><span class="special">(</span><span class="identifier">size_t</span> <span class="identifier">pos</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="keyword">const</span> <span class="identifier">charT</span><span class="special">&</span> <span class="identifier">front</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="keyword">const</span> <span class="identifier">charT</span><span class="special">&</span> <span class="identifier">back</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">BOOST_CONSTEXPR</span> <span class="keyword">const</span> <span class="identifier">charT</span><span class="special">*</span> <span class="identifier">data</span><span class="special">()</span> <span class="keyword">const</span> <span class="special">;</span>
+</pre>
+<p>
+ Modifying the <code class="computeroutput"><span class="identifier">string_ref</span></code> (but
+ not the underlying data):
+ </p>
+<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">clear</span><span class="special">();</span>
+<span class="keyword">void</span> <span class="identifier">remove_prefix</span><span class="special">(</span><span class="identifier">size_type</span> <span class="identifier">n</span><span class="special">);</span>
+<span class="keyword">void</span> <span class="identifier">remove_suffix</span><span class="special">(</span><span class="identifier">size_type</span> <span class="identifier">n</span><span class="special">);</span>
+</pre>
+<p>
+ Searching:
+ </p>
+<pre class="programlisting"><span class="identifier">size_type</span> <span class="identifier">find</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">s</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find</span><span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">rfind</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">s</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">rfind</span><span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find_first_of</span><span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find_last_of</span> <span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+
+<span class="identifier">size_type</span> <span class="identifier">find_first_of</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">s</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find_last_of</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">s</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find_first_not_of</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">s</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find_first_not_of</span><span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find_last_not_of</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">s</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="identifier">size_type</span> <span class="identifier">find_last_not_of</span><span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+</pre>
+<p>
+ String-like operations:
+ </p>
+<pre class="programlisting"><span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">basic_string_ref</span> <span class="identifier">substr</span><span class="special">(</span><span class="identifier">size_type</span> <span class="identifier">pos</span><span class="special">,</span> <span class="identifier">size_type</span> <span class="identifier">n</span><span class="special">=</span><span class="identifier">npos</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span> <span class="comment">// Creates a new string_ref</span>
+<span class="keyword">bool</span> <span class="identifier">starts_with</span><span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="keyword">bool</span> <span class="identifier">starts_with</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">x</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="keyword">bool</span> <span class="identifier">ends_with</span><span class="special">(</span><span class="identifier">charT</span> <span class="identifier">c</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+<span class="keyword">bool</span> <span class="identifier">ends_with</span><span class="special">(</span><span class="identifier">basic_string_ref</span> <span class="identifier">x</span><span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
+</pre>
+</div>
+<div class="section string_ref_history">
+<div class="titlepage"><div><div><h2 class="title" style="clear: both">
+<a name="string_ref.history"></a><a class="link" href="string_ref.html#string_ref.history" title="History">History</a>
+</h2></div></div></div>
+<h4>
+<a name="string_ref.history.h0"></a>
+ <span><a name="string_ref.history.boost_1_53"></a></span><a class="link" href="string_ref.html#string_ref.history.boost_1_53">boost
+ 1.53</a>
+ </h4>
+<div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem">
+ Introduced
+ </li></ul></div>
+</div>
+</div>
+<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
+<td align="left"><p><small>Last revised: January 14, 2013 at 16:24:14 GMT</small></p></td>
+<td align="right"><div class="copyright-footer"></div></td>
+</tr></table>
+<hr>
+<div class="spirit-nav"></div>
+</body>
+</html>
Modified: trunk/libs/utility/doc/string_ref.qbk
==============================================================================
--- trunk/libs/utility/doc/string_ref.qbk (original)
+++ trunk/libs/utility/doc/string_ref.qbk 2013-01-14 11:25:56 EST (Mon, 14 Jan 2013)
@@ -37,7 +37,7 @@
`string_ref` acts as a container; it includes all the methods that you would expect in a container, including iteration support, `operator []`, `at` and `size`. It can be used with any of the iterator-based algorithms in the STL - as long as you don't need to change the underlying data (`sort` and `remove`, for example, will not work)
-Besides generic container functionality, `string_ref` provides a subset of the interface of `std::string`. This makes it easy to replace parameters of type `const std::string &` with `boost::string_ref`.
+Besides generic container functionality, `string_ref` provides a subset of the interface of `std::string`. This makes it easy to replace parameters of type `const std::string &` with `boost::string_ref`. Like `std::string`, `string_ref` has a static member variable named `npos` to denote the result of failed searches, and to mean "the end".
Because a `string_ref` does not own the data that it "points to", it introduces lifetime issues into code that uses it. The programmer must ensure that the data that a `string_ref` refers to exists as long as the `string_ref` does.
@@ -50,12 +50,12 @@
Integrating `string_ref` into your code is fairly simple. Wherever you pass a `const std::string &` or `std::string` as a parameter, that's a candidate for passing a `boost::string_ref`.
- std::string extract_part ( const std::string &bar ) {
- return bar.substr ( 2, 3 );
- }
-
- if ( extract_part ( "ABCDEFG" ).front() == "C" ) { /* do something */ }
-
+ std::string extract_part ( const std::string &bar ) {
+ return bar.substr ( 2, 3 );
+ }
+
+ if ( extract_part ( "ABCDEFG" ).front() == "C" ) { /* do something */ }
+
Let's figure out what happens in this (contrived) example.
First, a temporary string is created from the string literal `"ABCDEFG"`, and it is passed (by reference) to the routine `extract_part`. Then a second string is created in the call `std::string::substr` and returned to `extract_part` (this copy may be elided by RVO). Then `extract_part` returns that string back to the caller (again this copy may be elided). The first temporary string is deallocated, and `front` is called on the second string, and then it is deallocated as well.
@@ -64,11 +64,11 @@
Now let's look at the same code with `string_ref`:
- boost::string_ref extract_part ( boost::string_ref bar ) {
- return bar.substr ( 2, 3 );
- }
-
- if ( extract_part ( "ABCDEFG" ).front() == "C" ) { /* do something */ }
+ boost::string_ref extract_part ( boost::string_ref bar ) {
+ return bar.substr ( 2, 3 );
+ }
+
+ if ( extract_part ( "ABCDEFG" ).front() == "C" ) { /* do something */ }
No memory allocations. No copying of character data. No changes to the code other than the types. There are two `string_ref`s created, and two `string_ref`s copied, but those are cheap operations.
@@ -83,6 +83,73 @@
`#include <boost/utility/string_ref.hpp>`
+Construction and copying:
+
+ BOOST_CONSTEXPR basic_string_ref (); // Constructs an empty string_ref
+ BOOST_CONSTEXPR basic_string_ref(const charT* str); // Constructs from a NULL-terminated string
+ BOOST_CONSTEXPR basic_string_ref(const charT* str, size_type len); // Constructs from a pointer, length pair
+ template<typename Allocator>
+ basic_string_ref(const std::basic_string<charT, traits, Allocator>& str); // Constructs from a std::string
+ basic_string_ref (const basic_string_ref &rhs);
+ basic_string_ref& operator=(const basic_string_ref &rhs);
+
+`string_ref` does not define a move constructor nor a move-assignment operator because copying a `string_ref` is just a cheap as moving one.
+
+Basic container-like functions:
+
+ BOOST_CONSTEXPR size_type size() const ;
+ BOOST_CONSTEXPR size_type length() const ;
+ BOOST_CONSTEXPR size_type max_size() const ;
+ BOOST_CONSTEXPR bool empty() const ;
+
+ // All iterators are const_iterators
+ BOOST_CONSTEXPR const_iterator begin() const ;
+ BOOST_CONSTEXPR const_iterator cbegin() const ;
+ BOOST_CONSTEXPR const_iterator end() const ;
+ BOOST_CONSTEXPR const_iterator cend() const ;
+ const_reverse_iterator rbegin() const ;
+ const_reverse_iterator crbegin() const ;
+ const_reverse_iterator rend() const ;
+ const_reverse_iterator crend() const ;
+
+Access to the individual elements (all of which are const):
+
+ BOOST_CONSTEXPR const charT& operator[](size_type pos) const ;
+ const charT& at(size_t pos) const ;
+ BOOST_CONSTEXPR const charT& front() const ;
+ BOOST_CONSTEXPR const charT& back() const ;
+ BOOST_CONSTEXPR const charT* data() const ;
+
+Modifying the `string_ref` (but not the underlying data):
+
+ void clear();
+ void remove_prefix(size_type n);
+ void remove_suffix(size_type n);
+
+Searching:
+
+ size_type find(basic_string_ref s) const ;
+ size_type find(charT c) const ;
+ size_type rfind(basic_string_ref s) const ;
+ size_type rfind(charT c) const ;
+ size_type find_first_of(charT c) const ;
+ size_type find_last_of (charT c) const ;
+
+ size_type find_first_of(basic_string_ref s) const ;
+ size_type find_last_of(basic_string_ref s) const ;
+ size_type find_first_not_of(basic_string_ref s) const ;
+ size_type find_first_not_of(charT c) const ;
+ size_type find_last_not_of(basic_string_ref s) const ;
+ size_type find_last_not_of(charT c) const ;
+
+String-like operations:
+
+ BOOST_CONSTEXPR basic_string_ref substr(size_type pos, size_type n=npos) const ; // Creates a new string_ref
+ bool starts_with(charT c) const ;
+ bool starts_with(basic_string_ref x) const ;
+ bool ends_with(charT c) const ;
+ bool ends_with(basic_string_ref x) const ;
+
[endsect]
[/===============]
@@ -91,7 +158,7 @@
[heading boost 1.53]
* Introduced
-
+
[endsect]
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