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<html>
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<title>Generator Basics</title>
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<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="spirit.karma.reference.basics"></a><a class="link" href="basics.html" title="Generator Basics">Generator Basics</a>
</h4></div></div></div>
<h6>
<a name="spirit.karma.reference.basics.h0"></a>
          <span><a name="spirit.karma.reference.basics.lazy_argument"></a></span><a class="link" href="basics.html#spirit.karma.reference.basics.lazy_argument">Lazy
          Argument</a>
        </h6>
<p>
          Some generators (e.g. primitives and non-terminals) may take in additional
          attributes. Such generators take the form:
        </p>
<pre class="programlisting"><span class="identifier">g</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">g</span></code> is a generator.
          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 generator'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 <a class="link" href="../tutorials/semantic_actions.html" title="Generator Semantic Actions">Semantic
          Actions</a>).
        </p>
<h6>
<a name="spirit.karma.reference.basics.h1"></a>
          <span><a name="spirit.karma.reference.basics.character_encoding_namespace"></a></span><a class="link" href="basics.html#spirit.karma.reference.basics.character_encoding_namespace">Character
          Encoding Namespace</a>
        </h6>
<p>
          Some generators 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>
          generator works differently with ISO8859.1 and ASCII encodings. Where necessary,
          Spirit encodes (tags) the generator 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 generators 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 generator</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 karma sub-namespaces with the same names:
        </p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
              boost::spirit::karma::ascii
            </li>
<li class="listitem">
              boost::spirit::karma::iso8859_1
            </li>
<li class="listitem">
              boost::spirit::karma::standard
            </li>
<li class="listitem">
              boost::spirit::karma::standard_wide
            </li>
</ul></div>
<h6>
<a name="spirit.karma.reference.basics.h2"></a>
          <span><a name="spirit.karma.reference.basics.examples"></a></span><a class="link" href="basics.html#spirit.karma.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">&lt;</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">karma</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</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">support_utree</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</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">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</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">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</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">std_pair</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">iostream</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">string</span><span class="special">&gt;</span>
</pre>
<p>
        </p>
<p>
          The used output iterator:
        </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_insert_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">output_iterator_type</span><span class="special">;</span>
</pre>
<p>
        </p>
<p>
          Our test functions:
        </p>
<p>
          This one tests the generators without attributes.
        </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">G</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">test_generator</span><span class="special">(</span><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">G</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">g</span><span class="special">)</span>
<span class="special">{</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span><span class="special">;</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_insert_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">out</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span>
    <span class="keyword">if</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">karma</span><span class="special">::</span><span class="identifier">generate</span><span class="special">(</span><span class="identifier">out</span><span class="special">,</span> <span class="identifier">g</span><span class="special">)</span> <span class="special">&amp;&amp;</span> <span class="identifier">s</span> <span class="special">==</span> <span class="identifier">expected</span><span class="special">)</span>
        <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"ok"</span> <span class="special">&lt;&lt;</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">&lt;&lt;</span> <span class="string">"fail"</span> <span class="special">&lt;&lt;</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 test the generators with one or more user supplied attributes.
        </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">G</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">test_generator_attr</span><span class="special">(</span><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">G</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">attr</span><span class="special">)</span>
<span class="special">{</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span><span class="special">;</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_insert_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">out</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span>
    <span class="keyword">if</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">karma</span><span class="special">::</span><span class="identifier">generate</span><span class="special">(</span><span class="identifier">out</span><span class="special">,</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">attr</span><span class="special">)</span> <span class="special">&amp;&amp;</span> <span class="identifier">s</span> <span class="special">==</span> <span class="identifier">expected</span><span class="special">)</span>
        <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"ok"</span> <span class="special">&lt;&lt;</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">&lt;&lt;</span> <span class="string">"fail"</span> <span class="special">&lt;&lt;</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>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">G</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T2</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">test_generator_attr</span><span class="special">(</span><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">G</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">T1</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">attr1</span><span class="special">,</span>
    <span class="identifier">T2</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">attr2</span><span class="special">)</span>
<span class="special">{</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span><span class="special">;</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_insert_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">out</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span>
    <span class="keyword">if</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">karma</span><span class="special">::</span><span class="identifier">generate</span><span class="special">(</span><span class="identifier">out</span><span class="special">,</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">attr1</span><span class="special">,</span> <span class="identifier">attr2</span><span class="special">)</span> <span class="special">&amp;&amp;</span> <span class="identifier">s</span> <span class="special">==</span> <span class="identifier">expected</span><span class="special">)</span>
        <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"ok"</span> <span class="special">&lt;&lt;</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">&lt;&lt;</span> <span class="string">"fail"</span> <span class="special">&lt;&lt;</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>
          This tests the generators with one attribute and while using delimited
          output.
        </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">G</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Delimiter</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">test_generator_attr_delim</span><span class="special">(</span><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">G</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">Delimiter</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">d</span><span class="special">,</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">attr</span><span class="special">)</span>
<span class="special">{</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span><span class="special">;</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_insert_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">out</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span>
    <span class="keyword">if</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">karma</span><span class="special">::</span><span class="identifier">generate_delimited</span><span class="special">(</span><span class="identifier">out</span><span class="special">,</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">d</span><span class="special">,</span> <span class="identifier">attr</span><span class="special">)</span> <span class="special">&amp;&amp;</span> <span class="identifier">s</span> <span class="special">==</span> <span class="identifier">expected</span><span class="special">)</span>
        <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"ok"</span> <span class="special">&lt;&lt;</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">&lt;&lt;</span> <span class="string">"fail"</span> <span class="special">&lt;&lt;</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 examples of the binary generators use one or more of the following
          tests.
        </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">G</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">test_binary_generator</span><span class="special">(</span><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">size</span><span class="special">,</span> <span class="identifier">G</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">g</span><span class="special">)</span>
<span class="special">{</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span><span class="special">;</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_insert_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">out</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span>
    <span class="keyword">if</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">karma</span><span class="special">::</span><span class="identifier">generate</span><span class="special">(</span><span class="identifier">out</span><span class="special">,</span> <span class="identifier">g</span><span class="special">)</span> <span class="special">&amp;&amp;</span> <span class="special">!</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">memcmp</span><span class="special">(</span><span class="identifier">s</span><span class="special">.</span><span class="identifier">c_str</span><span class="special">(),</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">size</span><span class="special">))</span>
        <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"ok"</span> <span class="special">&lt;&lt;</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">&lt;&lt;</span> <span class="string">"fail"</span> <span class="special">&lt;&lt;</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>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">G</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">test_binary_generator_attr</span><span class="special">(</span><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">size</span><span class="special">,</span> <span class="identifier">G</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">attr</span><span class="special">)</span>
<span class="special">{</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">s</span><span class="special">;</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_insert_iterator</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span> <span class="identifier">out</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span>
    <span class="keyword">if</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">karma</span><span class="special">::</span><span class="identifier">generate</span><span class="special">(</span><span class="identifier">out</span><span class="special">,</span> <span class="identifier">g</span><span class="special">,</span> <span class="identifier">attr</span><span class="special">)</span> <span class="special">&amp;&amp;</span> <span class="special">!</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">memcmp</span><span class="special">(</span><span class="identifier">s</span><span class="special">.</span><span class="identifier">c_str</span><span class="special">(),</span> <span class="identifier">expected</span><span class="special">,</span> <span class="identifier">size</span><span class="special">))</span>
        <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"ok"</span> <span class="special">&lt;&lt;</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">&lt;&lt;</span> <span class="string">"fail"</span> <span class="special">&lt;&lt;</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>
<h6>
<a name="spirit.karma.reference.basics.h3"></a>
          <span><a name="spirit.karma.reference.basics.models"></a></span><a class="link" href="basics.html#spirit.karma.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">&lt;</span><span class="identifier">Char</span><span class="special">&gt;</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.Karma</em></span>
          usable to customize the behavior of generators 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>
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<td align="right"><div class="copyright-footer">Copyright &#169; 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>
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