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- <title>X3 Program Structure</title>
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- </div>
- <div class="section">
- <div class="titlepage"><div><div><h3 class="title">
- <a name="spirit_x3.tutorials.minimal"></a><a class="link" href="minimal.html" title="X3 Program Structure">X3 Program Structure</a>
- </h3></div></div></div>
- <p>
- As a prerequisite in understanding this tutorial, please review the previous
- <a class="link" href="employee.html" title="Employee - Parsing into structs">employee example</a>. This
- example builds on top of that example.
- </p>
- <p>
- So far, to keep things simple, all of the tutorial programs are self contained
- in one cpp file. In reality, you will want to separate various logical modules
- of the parser into separate cpp and header files, decoupling the interface
- from the implememtation.
- </p>
- <p>
- There are many ways to structure an X3 parser, but the "minimal"
- example in this tutorial shows the preferred way. This example basically
- reuses the same parser as the <a class="link" href="employee.html" title="Employee - Parsing into structs">employee
- example</a> for the sake of familiarity, but structured to allow separate
- compilation of the actual parser in its own definition file and cpp file.
- The cpp files, including main see only the header files --the interfaces.
- This is a good example on how X3 parsers are structured in a C++ application.
- </p>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h0"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.structure"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.structure">Structure</a>
- </h5>
- <p>
- The program is structured in a directory with the following header and cpp
- files:
- </p>
- <div class="informaltable"><table class="table">
- <colgroup>
- <col>
- <col>
- </colgroup>
- <thead><tr>
- <th>
- <p>
- <code class="computeroutput"><span class="identifier">File</span></code>
- </p>
- </th>
- <th>
- <p>
- Description
- </p>
- </th>
- </tr></thead>
- <tbody>
- <tr>
- <td>
- <p>
- <a href="../../../../../example/x3/minimal/ast.hpp" target="_top">ast.hpp</a>
- </p>
- </td>
- <td>
- <p>
- The AST
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <a href="../../../../../example/x3/minimal/ast_adapted.hpp" target="_top">ast_adapted.hpp</a>
- </p>
- </td>
- <td>
- <p>
- Fusion adapters
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <a href="../../../../../example/x3/minimal/config.hpp" target="_top">config.hpp</a>
- </p>
- </td>
- <td>
- <p>
- Configuration
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <a href="../../../../../example/x3/minimal/employee.hpp" target="_top">employee.hpp</a>
- </p>
- </td>
- <td>
- <p>
- Main parser API
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <a href="../../../../../example/x3/minimal/employee_def.hpp" target="_top">employee_def.hpp</a>
- </p>
- </td>
- <td>
- <p>
- Parser definitions
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <a href="../../../../../example/x3/minimal/employee.cpp" target="_top">employee.cpp</a>
- </p>
- </td>
- <td>
- <p>
- Parser instantiation
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <a href="../../../../../example/x3/minimal/main.cpp" target="_top">main.cpp</a>
- </p>
- </td>
- <td>
- <p>
- Main program
- </p>
- </td>
- </tr>
- </tbody>
- </table></div>
- <p>
- The contents of the files should already be familiar. It's essentially the
- same <a class="link" href="employee.html" title="Employee - Parsing into structs">employee example</a>.
- So I will skip the details on how the parser works and focus only on the
- features needed for refactoring the program into a modular structure suitable
- for real-world deployment.
- </p>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h1"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.ast"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.ast">AST</a>
- </h5>
- <p>
- We place the AST declaration here:
- </p>
- <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">client</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">ast</span>
- <span class="special">{</span>
- <span class="keyword">struct</span> <span class="identifier">employee</span>
- <span class="special">{</span>
- <span class="keyword">int</span> <span class="identifier">age</span><span class="special">;</span>
- <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">forename</span><span class="special">;</span>
- <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">surname</span><span class="special">;</span>
- <span class="keyword">double</span> <span class="identifier">salary</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">fusion</span><span class="special">::</span><span class="keyword">operator</span><span class="special"><<;</span>
- <span class="special">}}</span>
- </pre>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h2"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.fusion_adapters"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.fusion_adapters">Fusion
- adapters</a>
- </h5>
- <p>
- Here, we adapt the AST for Fusion, making it a first-class fusion citizen:
- </p>
- <pre class="programlisting"><span class="identifier">BOOST_FUSION_ADAPT_STRUCT</span><span class="special">(</span><span class="identifier">client</span><span class="special">::</span><span class="identifier">ast</span><span class="special">::</span><span class="identifier">employee</span><span class="special">,</span>
- <span class="identifier">age</span><span class="special">,</span> <span class="identifier">forename</span><span class="special">,</span> <span class="identifier">surname</span><span class="special">,</span> <span class="identifier">salary</span>
- <span class="special">)</span>
- </pre>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h3"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.main_parser_api"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.main_parser_api">Main
- parser API</a>
- </h5>
- <p>
- This is the main header file that all other cpp files need to include.
- </p>
- <a name="__tutorial_spirit_declare__"></a><h5>
- <a name="spirit_x3.tutorials.minimal.h4"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.boost_spirit_declare"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.boost_spirit_declare">BOOST_SPIRIT_DECLARE</a>
- </h5>
- <p>
- Remember <a class="link" href="roman.html#__tutorial_spirit_define__"><code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DEFINE</span></code></a>?
- If not, then you probably want to go back and review that section to get
- a better understanding of what's happening.
- </p>
- <p>
- Here in the header file, instead of <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DEFINE</span></code>,
- we use <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DECLARE</span></code>
- for the <span class="bold"><strong>top</strong></span> rule. Behind the scenes, what's
- actually happening is that we are declaring a <code class="computeroutput"><span class="identifier">parse_rule</span></code>
- function in the client namespace. For example, given a rule named <code class="computeroutput"><span class="identifier">my_rule</span></code>, <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DECLARE</span><span class="special">(</span><span class="identifier">my_rule</span><span class="special">)</span></code> expands to this code:
- </p>
- <pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Iterator</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Context</span><span class="special">></span>
- <span class="keyword">bool</span> <span class="identifier">parse_rule</span><span class="special">(</span>
- <span class="keyword">decltype</span><span class="special">(</span><span class="identifier">my_rule</span><span class="special">)</span>
- <span class="special">,</span> <span class="identifier">Iterator</span><span class="special">&</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">Iterator</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">last</span>
- <span class="special">,</span> <span class="identifier">Context</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">context</span><span class="special">,</span> <span class="keyword">decltype</span><span class="special">(</span><span class="identifier">my_rule</span><span class="special">)::</span><span class="identifier">attribute_type</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">);</span>
- </pre>
- <p>
- If you went back and reviewed <a class="link" href="roman.html#__tutorial_spirit_define__">BOOST_SPIRIT_DEFINE</a>,
- you'll see why it is exactly what we need to use for header files. <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DECLARE</span></code> generates function
- declarations that are meant to be placed in hpp (header) files while <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DEFINE</span></code> generates function
- definitions that are meant to be placed in cpp files.
- </p>
- <div class="note"><table border="0" summary="Note">
- <tr>
- <td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../images/note.png"></td>
- <th align="left">Note</th>
- </tr>
- <tr><td align="left" valign="top"><p>
- <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DECLARE</span></code> is
- variadic and may be used for one or more rules. Example: <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DECLARE</span><span class="special">(</span><span class="identifier">r1</span><span class="special">,</span> <span class="identifier">r2</span><span class="special">,</span> <span class="identifier">r3</span><span class="special">);</span></code>
- </p></td></tr>
- </table></div>
- <p>
- In this example, the top rule is <code class="computeroutput"><span class="identifier">employee</span></code>.
- We declare <code class="computeroutput"><span class="identifier">employee</span></code> in this
- header file:
- </p>
- <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">client</span>
- <span class="special">{</span>
- <span class="keyword">namespace</span> <span class="identifier">parser</span>
- <span class="special">{</span>
- <span class="keyword">namespace</span> <span class="identifier">x3</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">x3</span><span class="special">;</span>
- <span class="keyword">using</span> <span class="identifier">employee_type</span> <span class="special">=</span> <span class="identifier">x3</span><span class="special">::</span><span class="identifier">rule</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">employee</span><span class="special">,</span> <span class="identifier">ast</span><span class="special">::</span><span class="identifier">employee</span><span class="special">>;</span>
- <span class="identifier">BOOST_SPIRIT_DECLARE</span><span class="special">(</span><span class="identifier">employee_type</span><span class="special">);</span>
- <span class="special">}</span>
- <span class="identifier">parser</span><span class="special">::</span><span class="identifier">employee_type</span> <span class="identifier">employee</span><span class="special">();</span>
- <span class="special">}</span>
- </pre>
- <p>
- We also provide a function that returns an <code class="computeroutput"><span class="identifier">employee</span></code>
- object. This is the parser that we will use anywhere it is needed. X3 parser
- objects are very lightweight. They are basically simple tags with no data
- other than the name of the rule (e.g. "employee"). Notice that
- we are passing this by value.
- </p>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h5"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.parser_definitions"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.parser_definitions">Parser
- Definitions</a>
- </h5>
- <p>
- Here is where we place the actual rules that make up our grammar:
- </p>
- <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">parser</span>
- <span class="special">{</span>
- <span class="keyword">namespace</span> <span class="identifier">x3</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">x3</span><span class="special">;</span>
- <span class="keyword">namespace</span> <span class="identifier">ascii</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">x3</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">;</span>
- <span class="keyword">using</span> <span class="identifier">x3</span><span class="special">::</span><span class="identifier">int_</span><span class="special">;</span>
- <span class="keyword">using</span> <span class="identifier">x3</span><span class="special">::</span><span class="identifier">lit</span><span class="special">;</span>
- <span class="keyword">using</span> <span class="identifier">x3</span><span class="special">::</span><span class="identifier">double_</span><span class="special">;</span>
- <span class="keyword">using</span> <span class="identifier">x3</span><span class="special">::</span><span class="identifier">lexeme</span><span class="special">;</span>
- <span class="keyword">using</span> <span class="identifier">ascii</span><span class="special">::</span><span class="identifier">char_</span><span class="special">;</span>
- <span class="identifier">x3</span><span class="special">::</span><span class="identifier">rule</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">employee</span><span class="special">,</span> <span class="identifier">ast</span><span class="special">::</span><span class="identifier">employee</span><span class="special">></span> <span class="keyword">const</span> <span class="identifier">employee</span> <span class="special">=</span> <span class="string">"employee"</span><span class="special">;</span>
- <span class="keyword">auto</span> <span class="keyword">const</span> <span class="identifier">quoted_string</span> <span class="special">=</span> <span class="identifier">lexeme</span><span class="special">[</span><span class="char">'"'</span> <span class="special">>></span> <span class="special">+(</span><span class="identifier">char_</span> <span class="special">-</span> <span class="char">'"'</span><span class="special">)</span> <span class="special">>></span> <span class="char">'"'</span><span class="special">];</span>
- <span class="keyword">auto</span> <span class="keyword">const</span> <span class="identifier">employee_def</span> <span class="special">=</span>
- <span class="identifier">lit</span><span class="special">(</span><span class="string">"employee"</span><span class="special">)</span>
- <span class="special">>></span> <span class="char">'{'</span>
- <span class="special">>></span> <span class="identifier">int_</span> <span class="special">>></span> <span class="char">','</span>
- <span class="special">>></span> <span class="identifier">quoted_string</span> <span class="special">>></span> <span class="char">','</span>
- <span class="special">>></span> <span class="identifier">quoted_string</span> <span class="special">>></span> <span class="char">','</span>
- <span class="special">>></span> <span class="identifier">double_</span>
- <span class="special">>></span> <span class="char">'}'</span>
- <span class="special">;</span>
- <span class="identifier">BOOST_SPIRIT_DEFINE</span><span class="special">(</span><span class="identifier">employee</span><span class="special">);</span>
- <span class="special">}</span>
- <span class="identifier">parser</span><span class="special">::</span><span class="identifier">employee_type</span> <span class="identifier">employee</span><span class="special">()</span>
- <span class="special">{</span>
- <span class="keyword">return</span> <span class="identifier">parser</span><span class="special">::</span><span class="identifier">employee</span><span class="special">;</span>
- <span class="special">}</span>
- </pre>
- <p>
- In the parser definition, we use <a class="link" href="roman.html#__tutorial_spirit_define__"><code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DEFINE</span></code></a> just like we
- did in the <a class="link" href="employee.html" title="Employee - Parsing into structs">employee example</a>.
- </p>
- <p>
- While this is another header file, it is not meant to be included by the
- client. Its purpose is to be included by an instantiations cpp file (see
- below). We place this in an <code class="computeroutput"><span class="special">.</span><span class="identifier">hpp</span></code> file for flexibility, so we have the
- freedom to instantiate the parser with different iterator types.
- </p>
- <a name="tutorial_configuration"></a><h5>
- <a name="spirit_x3.tutorials.minimal.h6"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.configuration"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.configuration">Configuration</a>
- </h5>
- <p>
- Here, we declare some types for instatntaiting our X3 parser with. Rememeber
- that Spirit parsers can work with any <a href="http://en.cppreference.com/w/cpp/named_req/ForwardIterator" target="_top"><code class="computeroutput"><span class="identifier">ForwardIterator</span></code></a>. We'll also need
- to provide the initial context type. This is the context that X3 will use
- to initiate a parse. For calling <code class="computeroutput"><span class="identifier">phrase_parse</span></code>,
- you will need the <code class="computeroutput"><span class="identifier">phrase_parse_context</span></code>
- like we do below, passing in the skipper type.
- </p>
- <pre class="programlisting"><span class="keyword">using</span> <span class="identifier">iterator_type</span> <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">::</span><span class="identifier">const_iterator</span><span class="special">;</span>
- <span class="keyword">using</span> <span class="identifier">context_type</span> <span class="special">=</span> <span class="identifier">x3</span><span class="special">::</span><span class="identifier">phrase_parse_context</span><span class="special"><</span><span class="identifier">x3</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">::</span><span class="identifier">space_type</span><span class="special">>::</span><span class="identifier">type</span><span class="special">;</span>
- </pre>
- <p>
- For plain <code class="computeroutput"><span class="identifier">parse</span></code>, we simply
- use <code class="computeroutput"><span class="identifier">x3</span><span class="special">::</span><span class="identifier">unused_type</span></code>.
- </p>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h7"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.parser_instantiation"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.parser_instantiation">Parser
- Instantiation</a>
- </h5>
- <p>
- Now we instantiate our parser here, for our specific configuration:
- </p>
- <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">client</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">parser</span>
- <span class="special">{</span>
- <span class="identifier">BOOST_SPIRIT_INSTANTIATE</span><span class="special">(</span><span class="identifier">employee_type</span><span class="special">,</span> <span class="identifier">iterator_type</span><span class="special">,</span> <span class="identifier">context_type</span><span class="special">);</span>
- <span class="special">}}</span>
- </pre>
- <p>
- For that, we use <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_INSTANTIATE</span></code>,
- passing in the parser type, the iterator type, and the context type.
- </p>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h8"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.boost_spirit_instantiate"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.boost_spirit_instantiate">BOOST_SPIRIT_INSTANTIATE</a>
- </h5>
- <p>
- Go back and review <a class="link" href="roman.html#__tutorial_spirit_define__"><code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DEFINE</span></code></a> and <a class="link" href="minimal.html#__tutorial_spirit_declare__"><code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DECLARE</span></code></a> to get a better
- grasp of what's happening with <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_INSTANTIATE</span></code>
- and why it is needed.
- </p>
- <p>
- So what the heck is <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_INSTANTIATE</span></code>?
- What we want is to isolate the instantiation of our parsers (rules and all
- that), into separate translation units (or cpp files, if you will). In this
- example, we want to place our x3 employee stuff in <a href="../../../../../example/x3/minimal/employee.cpp" target="_top">employee.cpp</a>.
- That way, we have separate compilation. Every time we update our employee
- parser source code, we only have to build the <code class="computeroutput"><span class="identifier">employee</span><span class="special">.</span><span class="identifier">cpp</span></code> file.
- All the rest will not be affected. By compiling only once in one translation
- unit, we save on build times and avoid code bloat. There is no code duplication,
- which can happen otherwise if you simply include the employee parser (<a href="../../../../../example/x3/minimal/employee.hpp" target="_top">employee.hpp</a>) everywhere.
- </p>
- <p>
- But how do you do that. Remember that our parser definitions are also placed
- in its own header file for flexibility, so we have the freedom to instantiate
- the parser with different iterator types.
- </p>
- <p>
- What we need to do is explicitly instantiate the <code class="computeroutput"><span class="identifier">parse_rule</span></code>
- function we declared and defined via <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DECLARE</span></code>
- and <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_DEFINE</span></code> respectively,
- using <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_INSTANTIATE</span></code>.
- For our particular example, <code class="computeroutput"><span class="identifier">BOOST_SPIRIT_INSTANTIATE</span></code>
- expands to this code:
- </p>
- <pre class="programlisting"><span class="keyword">template</span> <span class="keyword">bool</span> <span class="identifier">parse_rule</span><span class="special"><</span><span class="identifier">iterator_type</span><span class="special">,</span> <span class="identifier">context_type</span><span class="special">>(</span>
- <span class="identifier">employee_type</span> <span class="identifier">rule_</span>
- <span class="special">,</span> <span class="identifier">iterator_type</span><span class="special">&</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">iterator_type</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">last</span>
- <span class="special">,</span> <span class="identifier">context_type</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">context</span><span class="special">,</span> <span class="identifier">employee_type</span><span class="special">::</span><span class="identifier">attribute_type</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">);</span>
- </pre>
- <h5>
- <a name="spirit_x3.tutorials.minimal.h9"></a>
- <span class="phrase"><a name="spirit_x3.tutorials.minimal.main_program"></a></span><a class="link" href="minimal.html#spirit_x3.tutorials.minimal.main_program">Main
- Program</a>
- </h5>
- <p>
- Finally, we have our main program. The code is the same as single cpp file
- <a class="link" href="employee.html" title="Employee - Parsing into structs">employee example</a>, but
- here, we simply include three header files:
- </p>
- <pre class="programlisting"><span class="preprocessor">#include</span> <span class="string">"ast.hpp"</span>
- <span class="preprocessor">#include</span> <span class="string">"ast_adapted.hpp"</span>
- <span class="preprocessor">#include</span> <span class="string">"employee.hpp"</span>
- </pre>
- <div class="orderedlist"><ol class="orderedlist" type="1">
- <li class="listitem">
- <code class="computeroutput"><span class="identifier">ast</span><span class="special">.</span><span class="identifier">hpp</span></code> for the AST declaration
- </li>
- <li class="listitem">
- <code class="computeroutput"><span class="identifier">ast_adapted</span><span class="special">.</span><span class="identifier">hpp</span></code> if you need to traverse the AST
- using fusion
- </li>
- <li class="listitem">
- <code class="computeroutput"><span class="identifier">employee</span><span class="special">.</span><span class="identifier">hpp</span></code> the main parser API
- </li>
- </ol></div>
- </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 © 2001-2018 Joel de Guzman,
- Hartmut Kaiser<p>
- Distributed under the Boost Software License, Version 1.0. (See accompanying
- file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
- </p>
- </div></td>
- </tr></table>
- <hr>
- <div class="spirit-nav">
- <a accesskey="p" href="employee.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../tutorials.html"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="annotation.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a>
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