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<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="spirit.qi.reference.basics"></a><a class="link" href="basics.html" title="Basics">Basics</a>
</h4></div></div></div>
<a name="spirit.qi.reference.basics.lazy_argument"></a><h6>
<a name="id888328"></a>
<a class="link" href="basics.html#spirit.qi.reference.basics.lazy_argument">Lazy Argument</a>
</h6>
<p>
Some parsers (e.g. primitives and non-terminals) may take in additional
attributes. Such parsers take the form:
</p>
<pre class="programlisting"><span class="identifier">p</span><span class="special">(</span><span class="identifier">a1</span><span class="special">,</span> <span class="identifier">a2</span><span class="special">,...,</span> <span class="identifier">aN</span><span class="special">)</span>
</pre>
<p>
where <code class="computeroutput"><span class="identifier">p</span></code> is a parser. Each
of the arguments (a1 ... aN) can either be an immediate value, or a function,
<code class="computeroutput"><span class="identifier">f</span></code>, with signature:
</p>
<pre class="programlisting"><span class="identifier">T</span> <span class="identifier">f</span><span class="special">(</span><span class="identifier">Unused</span><span class="special">,</span> <span class="identifier">Context</span><span class="special">)</span>
</pre>
<p>
where <code class="computeroutput"><span class="identifier">T</span></code>, the function's
return value, is compatible with the argument type expected and <code class="computeroutput"><span class="identifier">Context</span></code> is the parser's Context type
(The first argument is <code class="computeroutput"><span class="identifier">unused</span></code>
to make the <code class="computeroutput"><span class="identifier">Context</span></code> the
second argument. This is done for uniformity with Semantic Actions).
</p>
<a name="spirit.qi.reference.basics.character_encoding_namespace"></a><h6>
<a name="id888464"></a>
<a class="link" href="basics.html#spirit.qi.reference.basics.character_encoding_namespace">Character
Encoding Namespace</a>
</h6>
<p>
Some parsers need to know which character set a <code class="computeroutput"><span class="keyword">char</span></code>
or <code class="computeroutput"><span class="keyword">wchar_t</span></code> is operating on.
For example, the <code class="computeroutput"><span class="identifier">alnum</span></code>
parser works differently with ISO8859.1 and ASCII encodings. Where necessary,
Spirit encodes (tags) the parser with the character set.
</p>
<p>
We have a namespace for each character set Spirit will be supporting. That
includes <code class="computeroutput"><span class="identifier">ascii</span></code>, <code class="computeroutput"><span class="identifier">iso8859_1</span></code>, <code class="computeroutput"><span class="identifier">standard</span></code>
and <code class="computeroutput"><span class="identifier">standard_wide</span></code> (and
in the future, <code class="computeroutput"><span class="identifier">unicode</span></code>).
In each of the character encoding namespaces, we place tagged versions
of parsers such as <code class="computeroutput"><span class="identifier">alnum</span></code>,
<code class="computeroutput"><span class="identifier">space</span></code> etc.
</p>
<p>
Example:
</p>
<pre class="programlisting"><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">ascii</span><span class="special">::</span><span class="identifier">space</span><span class="special">;</span> <span class="comment">// use the ASCII space parser
</span></pre>
<p>
Namespaces:
</p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
boost::spirit::ascii
</li>
<li class="listitem">
boost::spirit::iso8859_1
</li>
<li class="listitem">
boost::spirit::standard
</li>
<li class="listitem">
boost::spirit::standard_wide
</li>
</ul></div>
<p>
For ease of use, the components in this namespaces are also brought into
the qi sub-namespaces with the same names:
</p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
boost::spirit::qi::ascii
</li>
<li class="listitem">
boost::spirit::qi::iso8859_1
</li>
<li class="listitem">
boost::spirit::qi::standard
</li>
<li class="listitem">
boost::spirit::qi::standard_wide
</li>
</ul></div>
<a name="spirit.qi.reference.basics.examples"></a><h6>
<a name="id888679"></a>
<a class="link" href="basics.html#spirit.qi.reference.basics.examples">Examples</a>
</h6>
<p>
All sections in the reference present some real world examples. The examples
use a common test harness to keep the example code as minimal and direct
to the point as possible. The test harness is presented below.
</p>
<p>
Some includes:
</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">include</span><span class="special">/</span><span class="identifier">phoenix_core</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">include</span><span class="special">/</span><span class="identifier">phoenix_operator</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">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">adapt_struct</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">iostream</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">string</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">cstdlib</span><span class="special">></span>
</pre>
<p>
</p>
<p>
Our test functions:
</p>
<p>
These functions test the parsers without attributes.
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">P</span><span class="special">></span>
<span class="keyword">void</span> <span class="identifier">test_parser</span><span class="special">(</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">input</span><span class="special">,</span> <span class="identifier">P</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">p</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">full_match</span> <span class="special">=</span> <span class="keyword">true</span><span class="special">)</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">qi</span><span class="special">::</span><span class="identifier">parse</span><span class="special">;</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">f</span><span class="special">(</span><span class="identifier">input</span><span class="special">);</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">l</span><span class="special">(</span><span class="identifier">f</span> <span class="special">+</span> <span class="identifier">strlen</span><span class="special">(</span><span class="identifier">f</span><span class="special">));</span>
<span class="keyword">if</span> <span class="special">(</span><span class="identifier">parse</span><span class="special">(</span><span class="identifier">f</span><span class="special">,</span> <span class="identifier">l</span><span class="special">,</span> <span class="identifier">p</span><span class="special">)</span> <span class="special">&&</span> <span class="special">(!</span><span class="identifier">full_match</span> <span class="special">||</span> <span class="special">(</span><span class="identifier">f</span> <span class="special">==</span> <span class="identifier">l</span><span class="special">)))</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"ok"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="keyword">else</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"fail"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="special">}</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">P</span><span class="special">></span>
<span class="keyword">void</span> <span class="identifier">test_phrase_parser</span><span class="special">(</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">input</span><span class="special">,</span> <span class="identifier">P</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">p</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">full_match</span> <span class="special">=</span> <span class="keyword">true</span><span class="special">)</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">qi</span><span class="special">::</span><span class="identifier">phrase_parse</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">qi</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">::</span><span class="identifier">space</span><span class="special">;</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">f</span><span class="special">(</span><span class="identifier">input</span><span class="special">);</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">l</span><span class="special">(</span><span class="identifier">f</span> <span class="special">+</span> <span class="identifier">strlen</span><span class="special">(</span><span class="identifier">f</span><span class="special">));</span>
<span class="keyword">if</span> <span class="special">(</span><span class="identifier">phrase_parse</span><span class="special">(</span><span class="identifier">f</span><span class="special">,</span> <span class="identifier">l</span><span class="special">,</span> <span class="identifier">p</span><span class="special">,</span> <span class="identifier">space</span><span class="special">)</span> <span class="special">&&</span> <span class="special">(!</span><span class="identifier">full_match</span> <span class="special">||</span> <span class="special">(</span><span class="identifier">f</span> <span class="special">==</span> <span class="identifier">l</span><span class="special">)))</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"ok"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="keyword">else</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"fail"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="special">}</span>
</pre>
<p>
</p>
<p>
These functions test the parsers with user supplied attributes.
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">P</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">></span>
<span class="keyword">void</span> <span class="identifier">test_parser_attr</span><span class="special">(</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">input</span><span class="special">,</span> <span class="identifier">P</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">p</span><span class="special">,</span> <span class="identifier">T</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">full_match</span> <span class="special">=</span> <span class="keyword">true</span><span class="special">)</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">qi</span><span class="special">::</span><span class="identifier">parse</span><span class="special">;</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">f</span><span class="special">(</span><span class="identifier">input</span><span class="special">);</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">l</span><span class="special">(</span><span class="identifier">f</span> <span class="special">+</span> <span class="identifier">strlen</span><span class="special">(</span><span class="identifier">f</span><span class="special">));</span>
<span class="keyword">if</span> <span class="special">(</span><span class="identifier">parse</span><span class="special">(</span><span class="identifier">f</span><span class="special">,</span> <span class="identifier">l</span><span class="special">,</span> <span class="identifier">p</span><span class="special">,</span> <span class="identifier">attr</span><span class="special">)</span> <span class="special">&&</span> <span class="special">(!</span><span class="identifier">full_match</span> <span class="special">||</span> <span class="special">(</span><span class="identifier">f</span> <span class="special">==</span> <span class="identifier">l</span><span class="special">)))</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"ok"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="keyword">else</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"fail"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="special">}</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">P</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">></span>
<span class="keyword">void</span> <span class="identifier">test_phrase_parser_attr</span><span class="special">(</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">input</span><span class="special">,</span> <span class="identifier">P</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">p</span><span class="special">,</span> <span class="identifier">T</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">,</span> <span class="keyword">bool</span> <span class="identifier">full_match</span> <span class="special">=</span> <span class="keyword">true</span><span class="special">)</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">qi</span><span class="special">::</span><span class="identifier">phrase_parse</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">qi</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">::</span><span class="identifier">space</span><span class="special">;</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">f</span><span class="special">(</span><span class="identifier">input</span><span class="special">);</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">l</span><span class="special">(</span><span class="identifier">f</span> <span class="special">+</span> <span class="identifier">strlen</span><span class="special">(</span><span class="identifier">f</span><span class="special">));</span>
<span class="keyword">if</span> <span class="special">(</span><span class="identifier">phrase_parse</span><span class="special">(</span><span class="identifier">f</span><span class="special">,</span> <span class="identifier">l</span><span class="special">,</span> <span class="identifier">p</span><span class="special">,</span> <span class="identifier">space</span><span class="special">,</span> <span class="identifier">attr</span><span class="special">)</span> <span class="special">&&</span> <span class="special">(!</span><span class="identifier">full_match</span> <span class="special">||</span> <span class="special">(</span><span class="identifier">f</span> <span class="special">==</span> <span class="identifier">l</span><span class="special">)))</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"ok"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="keyword">else</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"fail"</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="special">}</span>
</pre>
<p>
</p>
<p>
The <code class="computeroutput"><span class="identifier">print_info</span></code> utility
function prints information contained in the <code class="computeroutput"><span class="identifier">info</span></code>
class.
</p>
<p>
</p>
<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">printer</span>
<span class="special">{</span>
<span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">utf8_string</span> <span class="identifier">string</span><span class="special">;</span>
<span class="keyword">void</span> <span class="identifier">element</span><span class="special">(</span><span class="identifier">string</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">tag</span><span class="special">,</span> <span class="identifier">string</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">value</span><span class="special">,</span> <span class="keyword">int</span> <span class="identifier">depth</span><span class="special">)</span> <span class="keyword">const</span>
<span class="special">{</span>
<span class="keyword">for</span> <span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> <span class="identifier">i</span> <span class="special"><</span> <span class="special">(</span><span class="identifier">depth</span><span class="special">*</span><span class="number">4</span><span class="special">);</span> <span class="special">++</span><span class="identifier">i</span><span class="special">)</span> <span class="comment">// indent to depth
</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="char">' '</span><span class="special">;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"tag: "</span> <span class="special"><<</span> <span class="identifier">tag</span><span class="special">;</span>
<span class="keyword">if</span> <span class="special">(</span><span class="identifier">value</span> <span class="special">!=</span> <span class="string">""</span><span class="special">)</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">", value: "</span> <span class="special"><<</span> <span class="identifier">value</span><span class="special">;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="special">}</span>
<span class="special">};</span>
<span class="keyword">void</span> <span class="identifier">print_info</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">info</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">what</span><span class="special">)</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">basic_info_walker</span><span class="special">;</span>
<span class="identifier">printer</span> <span class="identifier">pr</span><span class="special">;</span>
<span class="identifier">basic_info_walker</span><span class="special"><</span><span class="identifier">printer</span><span class="special">></span> <span class="identifier">walker</span><span class="special">(</span><span class="identifier">pr</span><span class="special">,</span> <span class="identifier">what</span><span class="special">.</span><span class="identifier">tag</span><span class="special">,</span> <span class="number">0</span><span class="special">);</span>
<span class="identifier">boost</span><span class="special">::</span><span class="identifier">apply_visitor</span><span class="special">(</span><span class="identifier">walker</span><span class="special">,</span> <span class="identifier">what</span><span class="special">.</span><span class="identifier">value</span><span class="special">);</span>
<span class="special">}</span>
</pre>
<p>
</p>
<a name="spirit.qi.reference.basics.string"></a><h6>
<a name="id892372"></a>
<a class="link" href="basics.html#spirit.qi.reference.basics.string">String</a>
</h6>
<a name="spirit.qi.reference.basics.header"></a><h6>
<a name="id892386"></a>
<a class="link" href="basics.html#spirit.qi.reference.basics.header">Header</a>
</h6>
<pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/support/string_traits.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">support_string_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
</pre>
<p>
A string can be any object <code class="computeroutput"><span class="identifier">s</span></code>,
of type, <code class="computeroutput"><span class="identifier">S</span></code>, that satisfies
the following expression traits:
</p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
Expression
</p>
</th>
<th>
<p>
Semantics
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_string</span><span class="special"><</span><span class="identifier">S</span><span class="special">></span></code>
</p>
</td>
<td>
<p>
Metafunction that evaluates to <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code>
if a certain type, <code class="computeroutput"><span class="identifier">S</span></code>
is a string, <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">false_</span></code>
otherwise (See <a href="../../../../../../../libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL
Boolean Constant</a>).
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">traits</span><span class="special">::</span><span class="identifier">char_type_of</span><span class="special"><</span><span class="identifier">S</span><span class="special">></span></code>
</p>
</td>
<td>
<p>
Metafunction that returns the underlying char type of a string
type, <code class="computeroutput"><span class="identifier">S</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">traits</span><span class="special">::</span><span class="identifier">get_c_string</span><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
Function that returns the underlying raw C-string from <code class="computeroutput"><span class="identifier">s</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">traits</span><span class="special">::</span><span class="identifier">get_begin</span><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
Function that returns an <a href="http://www.sgi.com/tech/stl/" target="_top">STL</a>
iterator from <code class="computeroutput"><span class="identifier">s</span></code>
that points to the beginning the string.
</p>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">traits</span><span class="special">::</span><span class="identifier">get_end</span><span class="special">(</span><span class="identifier">s</span><span class="special">)</span></code>
</p>
</td>
<td>
<p>
Function that returns an <a href="http://www.sgi.com/tech/stl/" target="_top">STL</a>
iterator from <code class="computeroutput"><span class="identifier">s</span></code>
that points to the end of the string.
</p>
</td>
</tr>
</tbody>
</table></div>
<a name="spirit.qi.reference.basics.models"></a><h6>
<a name="id892866"></a>
<a class="link" href="basics.html#spirit.qi.reference.basics.models">Models</a>
</h6>
<p>
Predefined models include:
</p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
any literal string, e.g. "Hello, World",
</li>
<li class="listitem">
a pointer/reference to a null-terminated array of characters
</li>
<li class="listitem">
a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_string</span><span class="special"><</span><span class="identifier">Char</span><span class="special">></span></code>
</li>
</ul></div>
<p>
The namespace <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">traits</span></code> is open for users to provide their
own specializations. The customization points implemented by <span class="emphasis"><em>Spirit.Qi</em></span>
usable to customize the behavior of parsers are described in the section
<a class="link" href="../../advanced/customize.html" title="Customization of Spirit's Attribute Handling">Customization of Attribute Handling</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 © 2001-2010 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>
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