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| author | Anas Nashif <anas.nashif@intel.com> | 2012-10-30 12:57:26 -0700 |
|---|---|---|
| committer | Anas Nashif <anas.nashif@intel.com> | 2012-10-30 12:57:26 -0700 |
| commit | 1a78a62555be32868418fe52f8e330c9d0f95d5a (patch) | |
| tree | d3765a80e7d3b9640ec2e930743630cd6b9fce2b /libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/distinct.html | |
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Imported Upstream version 1.49.0upstream/1.49.0
Diffstat (limited to 'libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/distinct.html')
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diff --git a/libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/distinct.html b/libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/distinct.html new file mode 100755 index 0000000000..d79269f778 --- /dev/null +++ b/libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/distinct.html @@ -0,0 +1,325 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Qi Distinct Parser Directive</title> +<link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> +<link rel="home" href="../../../index.html" title="Spirit Repository 0.2"> +<link rel="up" href="../directives.html" title="Qi Parser Directives"> +<link rel="prev" href="confix.html" title="Qi Confix Parser Directive"> +<link rel="next" href="kwd.html" title="Qi Keyword Parser Directive"> +</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="confix.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../directives.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="kwd.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h4 class="title"> +<a name="spirit_repository.qi_components.directives.distinct"></a><a class="link" href="distinct.html" title="Qi Distinct Parser Directive">Qi + Distinct Parser Directive</a> +</h4></div></div></div> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h0"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.description"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.description">Description</a> + </h6> +<p> + The <span class="emphasis"><em>Spirit.Qi</em></span> <code class="computeroutput"><span class="identifier">distinct</span></code> + parser is a directive component allowing to avoid partial matches while + parsing using a skipper. A simple example is the common task of matching + a C keyword. Consider: + </p> +<pre class="programlisting"><span class="string">"description"</span> <span class="special">>></span> <span class="special">-</span><span class="identifier">lit</span><span class="special">(</span><span class="string">":"</span><span class="special">)</span> <span class="special">>></span> <span class="special">*(</span><span class="identifier">char_</span> <span class="special">-</span> <span class="identifier">eol</span><span class="special">)</span> +</pre> +<p> + intended to match a line in a configuration file. Let's assume further, + that this rule is used with a <code class="computeroutput"><span class="identifier">space</span></code> + skipper and that we have the following strings in the input: + </p> +<pre class="programlisting"><span class="string">"description: ident\n"</span> +<span class="string">"description ident\n"</span> +<span class="string">"descriptionident\n"</span> +</pre> +<p> + It might seem unexpected, but the parser above matches all three inputs + just fine, even if the third input should not match at all! In order to + avoid the unwanted match we are forced to make our rule more complicated: + </p> +<pre class="programlisting"><span class="identifier">lexeme</span><span class="special">[</span><span class="string">"description"</span> <span class="special">>></span> <span class="special">!</span><span class="identifier">char_</span><span class="special">(</span><span class="string">"a-zA-Z_0-9"</span><span class="special">)]</span> <span class="special">>></span> <span class="special">-</span><span class="identifier">lit</span><span class="special">(</span><span class="string">":"</span><span class="special">)</span> <span class="special">>></span> <span class="special">*(</span><span class="identifier">char_</span> <span class="special">-</span> <span class="identifier">eol</span><span class="special">)</span> +</pre> +<p> + (the rule reads as: match <code class="computeroutput"><span class="string">"description"</span></code> + as long as it's not <span class="emphasis"><em>directly</em></span> followed by a valid identifier). + </p> +<p> + The <code class="computeroutput"><span class="identifier">distinct</span><span class="special">[]</span></code> + directive is meant to simplify the rule above: + </p> +<pre class="programlisting"><span class="identifier">distinct</span><span class="special">(</span><span class="identifier">char_</span><span class="special">(</span><span class="string">"a-zA-Z_0-9"</span><span class="special">))[</span><span class="string">"description"</span><span class="special">]</span> <span class="special">>></span> <span class="special">-</span><span class="identifier">lit</span><span class="special">(</span><span class="string">":"</span><span class="special">)</span> <span class="special">>></span> <span class="special">*(</span><span class="identifier">char_</span> <span class="special">-</span> <span class="identifier">eol</span><span class="special">)</span> +</pre> +<p> + Using the <code class="computeroutput"><span class="identifier">distinct</span><span class="special">[]</span></code> + component instead of the explicit sequence has the advantage of being able + to encapsulate the tail (i.e the <code class="computeroutput"><span class="identifier">char_</span><span class="special">(</span><span class="string">"a-zA-Z_0-9"</span><span class="special">)</span></code>) as a separate parser construct. The following + code snippet illustrates the idea (for the full code of this example please + see <a href="../../../../../test/qi/distinct.cpp" target="_top">distinct.cpp</a>): + </p> +<p> +</p> +<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">spirit</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">;</span> +<span class="keyword">namespace</span> <span class="identifier">ascii</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">;</span> +<span class="keyword">namespace</span> <span class="identifier">repo</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">repository</span><span class="special">;</span> + +<span class="comment">// Define metafunctions allowing to compute the type of the distinct()</span> +<span class="comment">// and ascii::char_() constructs</span> +<span class="keyword">namespace</span> <span class="identifier">traits</span> +<span class="special">{</span> + <span class="comment">// Metafunction allowing to get the type of any repository::distinct(...) </span> + <span class="comment">// construct</span> + <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Tail</span><span class="special">></span> + <span class="keyword">struct</span> <span class="identifier">distinct_spec</span> + <span class="special">:</span> <span class="identifier">spirit</span><span class="special">::</span><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">terminal</span><span class="special"><</span><span class="identifier">repo</span><span class="special">::</span><span class="identifier">tag</span><span class="special">::</span><span class="identifier">distinct</span><span class="special">(</span><span class="identifier">Tail</span><span class="special">)></span> + <span class="special">{};</span> + + <span class="comment">// Metafunction allowing to get the type of any ascii::char_(...) construct</span> + <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">String</span><span class="special">></span> + <span class="keyword">struct</span> <span class="identifier">char_spec</span> + <span class="special">:</span> <span class="identifier">spirit</span><span class="special">::</span><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">terminal</span><span class="special"><</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">tag</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">String</span><span class="special">)></span> + <span class="special">{};</span> +<span class="special">};</span> + +<span class="comment">// Define a helper function allowing to create a distinct() construct from </span> +<span class="comment">// an arbitrary tail parser</span> +<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Tail</span><span class="special">></span> +<span class="keyword">inline</span> <span class="keyword">typename</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">distinct_spec</span><span class="special"><</span><span class="identifier">Tail</span><span class="special">>::</span><span class="identifier">type</span> +<span class="identifier">distinct_spec</span><span class="special">(</span><span class="identifier">Tail</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">tail</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">return</span> <span class="identifier">repo</span><span class="special">::</span><span class="identifier">distinct</span><span class="special">(</span><span class="identifier">tail</span><span class="special">);</span> +<span class="special">}</span> + +<span class="comment">// Define a helper function allowing to create a ascii::char_() construct </span> +<span class="comment">// from an arbitrary string representation</span> +<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">String</span><span class="special">></span> +<span class="keyword">inline</span> <span class="keyword">typename</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">char_spec</span><span class="special"><</span><span class="identifier">String</span><span class="special">>::</span><span class="identifier">type</span> +<span class="identifier">char_spec</span><span class="special">(</span><span class="identifier">String</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">str</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">return</span> <span class="identifier">ascii</span><span class="special">::</span><span class="identifier">char_</span><span class="special">(</span><span class="identifier">str</span><span class="special">);</span> +<span class="special">}</span> + +<span class="comment">// the following constructs the type of a distinct_spec holding a</span> +<span class="comment">// charset("0-9a-zA-Z_") as its tail parser</span> +<span class="keyword">typedef</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">char_spec</span><span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">charset_tag_type</span><span class="special">;</span> +<span class="keyword">typedef</span> <span class="identifier">traits</span><span class="special">::</span><span class="identifier">distinct_spec</span><span class="special"><</span><span class="identifier">charset_tag_type</span><span class="special">>::</span><span class="identifier">type</span> <span class="identifier">keyword_tag_type</span><span class="special">;</span> + +<span class="comment">// Define a new Qi 'keyword' directive usable as a shortcut for a</span> +<span class="comment">// repository::distinct(char_(std::string("0-9a-zA-Z_")))</span> +<span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="keyword">const</span> <span class="identifier">keyword_spec</span><span class="special">(</span><span class="string">"0-9a-zA-Z_"</span><span class="special">);</span> +<span class="identifier">keyword_tag_type</span> <span class="keyword">const</span> <span class="identifier">keyword</span> <span class="special">=</span> <span class="identifier">distinct_spec</span><span class="special">(</span><span class="identifier">char_spec</span><span class="special">(</span><span class="identifier">keyword_spec</span><span class="special">));</span> +</pre> +<p> + </p> +<p> + These definitions define a new Qi parser recognizing keywords! This allows + to rewrite our declaration parser expression as: + </p> +<pre class="programlisting"><span class="identifier">keyword</span><span class="special">[</span><span class="string">"description"</span><span class="special">]</span> <span class="special">>></span> <span class="special">-</span><span class="identifier">lit</span><span class="special">(</span><span class="string">":"</span><span class="special">)</span> <span class="special">>></span> <span class="special">*(</span><span class="identifier">char_</span> <span class="special">-</span> <span class="identifier">eol</span><span class="special">)</span> +</pre> +<p> + which is much more readable and concise if compared to the original parser + expression. In addition the new <code class="computeroutput"><span class="identifier">keyword</span><span class="special">[]</span></code> directive has the advantage to be usable + for wrapping any parser expression, not only strings as in the example + above. + </p> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h1"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.header"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.header">Header</a> + </h6> +<pre class="programlisting"><span class="comment">// forwards to <boost/spirit/repository/home/qi/directive/distinct.hpp></span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">repository</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi_distinct</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> +</pre> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h2"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.synopsis"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.synopsis">Synopsis</a> + </h6> +<pre class="programlisting"><span class="identifier">distinct</span><span class="special">(</span><span class="identifier">tail</span><span class="special">)[</span><span class="identifier">subject</span><span class="special">]</span> +</pre> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h3"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.parameters"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.parameters">Parameters</a> + </h6> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + Parameter + </p> + </th> +<th> + <p> + Description + </p> + </th> +</tr></thead> +<tbody> +<tr> +<td> + <p> + <code class="computeroutput"><span class="identifier">tail</span></code> + </p> + </td> +<td> + <p> + The parser construct specifying what whould not follow the subject + in order to match the overall expression. + </p> + </td> +</tr> +<tr> +<td> + <p> + <code class="computeroutput"><span class="identifier">subject</span></code> + </p> + </td> +<td> + <p> + The parser construct to use to match the current input. The distinct + directive makes sure that no unexpected partial matches occur. + </p> + </td> +</tr> +</tbody> +</table></div> +<p> + All two parameters can be arbitrary complex parsers themselves. + </p> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h4"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.attribute"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.attribute">Attribute</a> + </h6> +<p> + The <code class="computeroutput"><span class="identifier">distinct</span></code> component + exposes the attribute type of its subject as its own attribute type. If + the <code class="computeroutput"><span class="identifier">subject</span></code> does not expose + any attribute (the type is <code class="computeroutput"><span class="identifier">unused_type</span></code>), + then the <code class="computeroutput"><span class="identifier">distinct</span></code> does + not expose any attribute either. + </p> +<pre class="programlisting"><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span><span class="special">,</span> <span class="identifier">b</span><span class="special">:</span> <span class="identifier">B</span> <span class="special">--></span> <span class="identifier">distinct</span><span class="special">(</span><span class="identifier">b</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">A</span> +</pre> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h5"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.example"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.example">Example</a> + </h6> +<p> + The following example shows simple use cases of the <code class="computeroutput"><span class="identifier">distinct</span></code> + parser. <a href="../../../../../example/qi/distinct.cpp" target="_top">distinct.cpp</a>) + </p> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h6"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.prerequisites"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.prerequisites">Prerequisites</a> + </h6> +<p> + In addition to the main header file needed to include the core components + implemented in <span class="emphasis"><em>Spirit.Qi</em></span> we add the header file needed + for the new <code class="computeroutput"><span class="identifier">distinct</span></code> generator. + </p> +<p> +</p> +<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">repository</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi_distinct</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> +</pre> +<p> + </p> +<p> + To make all the code below more readable we introduce the following namespaces. + </p> +<p> +</p> +<pre class="programlisting"><span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">;</span> +<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">;</span> +<span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">repository</span><span class="special">::</span><span class="identifier">distinct</span><span class="special">;</span> +</pre> +<p> + </p> +<h6> +<a name="spirit_repository.qi_components.directives.distinct.h7"></a> + <span><a name="spirit_repository.qi_components.directives.distinct.using_the_distinct_directive_to_match_keywords"></a></span><a class="link" href="distinct.html#spirit_repository.qi_components.directives.distinct.using_the_distinct_directive_to_match_keywords">Using + The Distinct Directive to Match keywords</a> + </h6> +<p> + We show several examples of how the <code class="computeroutput"><span class="identifier">distinct</span><span class="special">[]</span></code> directive can be used to force correct + behavior while matching keywords. The first two code snippets show the + correct matching of the <code class="computeroutput"><span class="identifier">description</span></code> + keyword (in this hypothetical example we allow keywords to be directly + followed by an optional <code class="computeroutput"><span class="string">"--"</span></code>): + </p> +<p> +</p> +<pre class="programlisting"><span class="special">{</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">str</span><span class="special">(</span><span class="string">"description ident"</span><span class="special">);</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">first</span><span class="special">(</span><span class="identifier">str</span><span class="special">.</span><span class="identifier">begin</span><span class="special">());</span> + <span class="keyword">bool</span> <span class="identifier">r</span> <span class="special">=</span> <span class="identifier">qi</span><span class="special">::</span><span class="identifier">phrase_parse</span><span class="special">(</span><span class="identifier">first</span><span class="special">,</span> <span class="identifier">str</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span> + <span class="special">,</span> <span class="identifier">distinct</span><span class="special">(</span><span class="identifier">alnum</span> <span class="special">|</span> <span class="char">'_'</span><span class="special">)[</span><span class="string">"description"</span><span class="special">]</span> <span class="special">>></span> <span class="special">-</span><span class="identifier">lit</span><span class="special">(</span><span class="string">"--"</span><span class="special">)</span> <span class="special">>></span> <span class="special">+(</span><span class="identifier">alnum</span> <span class="special">|</span> <span class="char">'_'</span><span class="special">)</span> + <span class="special">,</span> <span class="identifier">space</span><span class="special">);</span> + <span class="identifier">BOOST_ASSERT</span><span class="special">(</span><span class="identifier">r</span> <span class="special">&&</span> <span class="identifier">first</span> <span class="special">==</span> <span class="identifier">str</span><span class="special">.</span><span class="identifier">end</span><span class="special">());</span> +<span class="special">}</span> +</pre> +<p> + </p> +<p> +</p> +<pre class="programlisting"><span class="special">{</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">str</span><span class="special">(</span><span class="string">"description--ident"</span><span class="special">);</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">first</span><span class="special">(</span><span class="identifier">str</span><span class="special">.</span><span class="identifier">begin</span><span class="special">());</span> + <span class="keyword">bool</span> <span class="identifier">r</span> <span class="special">=</span> <span class="identifier">qi</span><span class="special">::</span><span class="identifier">phrase_parse</span><span class="special">(</span><span class="identifier">first</span><span class="special">,</span> <span class="identifier">str</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span> + <span class="special">,</span> <span class="identifier">distinct</span><span class="special">(</span><span class="identifier">alnum</span> <span class="special">|</span> <span class="char">'_'</span><span class="special">)[</span><span class="string">"description"</span><span class="special">]</span> <span class="special">>></span> <span class="special">-</span><span class="identifier">lit</span><span class="special">(</span><span class="string">"--"</span><span class="special">)</span> <span class="special">>></span> <span class="special">+(</span><span class="identifier">alnum</span> <span class="special">|</span> <span class="char">'_'</span><span class="special">)</span> + <span class="special">,</span> <span class="identifier">space</span><span class="special">);</span> + <span class="identifier">BOOST_ASSERT</span><span class="special">(</span><span class="identifier">r</span> <span class="special">&&</span> <span class="identifier">first</span> <span class="special">==</span> <span class="identifier">str</span><span class="special">.</span><span class="identifier">end</span><span class="special">());</span> +<span class="special">}</span> +</pre> +<p> + </p> +<p> + The last example shows that the <code class="computeroutput"><span class="identifier">distinct</span><span class="special">[]</span></code> parser component correctly refuses to + match "description-ident": + </p> +<p> +</p> +<pre class="programlisting"><span class="special">{</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">str</span><span class="special">(</span><span class="string">"description-ident"</span><span class="special">);</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">first</span><span class="special">(</span><span class="identifier">str</span><span class="special">.</span><span class="identifier">begin</span><span class="special">());</span> + <span class="keyword">bool</span> <span class="identifier">r</span> <span class="special">=</span> <span class="identifier">qi</span><span class="special">::</span><span class="identifier">phrase_parse</span><span class="special">(</span><span class="identifier">first</span><span class="special">,</span> <span class="identifier">str</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span> + <span class="special">,</span> <span class="identifier">distinct</span><span class="special">(</span><span class="identifier">alnum</span> <span class="special">|</span> <span class="char">'_'</span><span class="special">)[</span><span class="string">"description"</span><span class="special">]</span> <span class="special">>></span> <span class="special">-</span><span class="identifier">lit</span><span class="special">(</span><span class="string">"--"</span><span class="special">)</span> <span class="special">>></span> <span class="special">+(</span><span class="identifier">alnum</span> <span class="special">|</span> <span class="char">'_'</span><span class="special">)</span> + <span class="special">,</span> <span class="identifier">space</span><span class="special">);</span> + <span class="identifier">BOOST_ASSERT</span><span class="special">(!</span><span class="identifier">r</span> <span class="special">&&</span> <span class="identifier">first</span> <span class="special">==</span> <span class="identifier">str</span><span class="special">.</span><span class="identifier">begin</span><span class="special">());</span> +<span class="special">}</span> +</pre> +<p> + </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 © 2001-2011 Joel de Guzman, Hartmut Kaiser<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="confix.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../directives.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="kwd.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |