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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="id845643"></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="id845780"></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="id845995"></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="id848596"></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="id848609"></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="id849089"></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> |
| <hr> |
| <div class="spirit-nav"> |
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| </div> |
| </body> |
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