libs/spirit/doc/html/spirit/qi/reference/directive/as.html

   1 <html>
   2 <head>
   3 <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
   4 <title>Parser Directives Forcing Atomic Assignment (as&lt;T&gt;, as_string[], as_wstring[])</title>
   5 <link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css">
   6 <meta name="generator" content="DocBook XSL Stylesheets V1.76.1">
   7 <link rel="home" href="../../../../index.html" title="Spirit 2.5.2">
   8 <link rel="up" href="../directive.html" title="Parser Directives">
   9 <link rel="prev" href="hold.html" title="Parser Directive for Attribute Commit/Rollback (hold[])">
  10 <link rel="next" href="../nonterminal.html" title="Nonterminal Parsers">
  11 </head>
  12 <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
  13 <table cellpadding="2" width="100%"><tr>
  14 <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../../boost.png"></td>
  15 <td align="center"><a href="../../../../../../../../index.html">Home</a></td>
  16 <td align="center"><a href="../../../../../../../../libs/libraries.htm">Libraries</a></td>
  17 <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
  18 <td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
  19 <td align="center"><a href="../../../../../../../../more/index.htm">More</a></td>
  20 </tr></table>
  21 <hr>
  22 <div class="spirit-nav">
  23 <a accesskey="p" href="hold.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../directive.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="../nonterminal.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a>
  24 </div>
  25 <div class="section">
  26 <div class="titlepage"><div><div><h5 class="title">
  27 <a name="spirit.qi.reference.directive.as"></a><a class="link" href="as.html" title="Parser Directives Forcing Atomic Assignment (as&lt;T&gt;, as_string[], as_wstring[])">Parser Directives
  28           Forcing Atomic Assignment (<code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;,</span> <span class="identifier">as_string</span><span class="special">[],</span> <span class="identifier">as_wstring</span><span class="special">[]</span></code>)</a>
  29 </h5></div></div></div>
  30 <h6>
  31 <a name="spirit.qi.reference.directive.as.h0"></a>
  32             <span><a name="spirit.qi.reference.directive.as.description"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.description">Description</a>
  33           </h6>
  34 <p>
  35             The <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
  36             class forces the atomic assignment of it's subject's synthesized attribute.
  37             Usually, repetitive parsers (such as <a class="link" href="../operator/kleene.html" title="Kleene Parser (*a)">Kleene</a>,
  38             etc) or sequences exposing a <code class="computeroutput"><span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">&gt;</span></code> will assign elements to the container
  39             supplied as their synthesized attribute by calling <a class="link" href="../../../advanced/customize/store_value/push_back.html" title="Store a Parsed Attribute Value into a Container (Qi)"><code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">push_back_container</span></code></a> repeatedly.
  40             In some cases, this may be undesirable. The <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code> class creates a directive that will
  41             pass a temporary object of type <code class="computeroutput"><span class="identifier">T</span></code>
  42             to it's subject. If the subject parser passes, the temporary object will
  43             be assigned to the directive's supplied attribute with a single call
  44             to <a class="link" href="../../../advanced/customize/assign_to.html" title="Store a Parsed Attribute Value (Qi)"><code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">assign_to</span></code></a>. If the subject parser
  45             fails, the directive's attribute is not mutated.
  46           </p>
  47 <div class="note"><table border="0" summary="Note">
  48 <tr>
  49 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td>
  50 <th align="left">Note</th>
  51 </tr>
  52 <tr><td align="left" valign="top"><p>
  53               <code class="computeroutput"><span class="identifier">T</span></code> is required to be
  54               a container type. If <a class="link" href="../../../advanced/customize/is_container.html" title="Determine if a Type Should be Treated as a Container (Qi and Karma)"><code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">is_container</span></code></a> does not return
  55               true for <code class="computeroutput"><span class="identifier">T</span></code>, a compile-time
  56               error will occur.
  57             </p></td></tr>
  58 </table></div>
  59 <div class="note"><table border="0" summary="Note">
  60 <tr>
  61 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td>
  62 <th align="left">Note</th>
  63 </tr>
  64 <tr><td align="left" valign="top"><p>
  65               The <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
  66               implicitly causes commit/rollback semantics similar in nature to the
  67               <a class="link" href="hold.html" title="Parser Directive for Attribute Commit/Rollback (hold[])"><code class="computeroutput"><span class="identifier">hold</span></code></a>
  68               directive.
  69             </p></td></tr>
  70 </table></div>
  71 <div class="caution"><table border="0" summary="Caution">
  72 <tr>
  73 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../../../../images/caution.png"></td>
  74 <th align="left">Caution</th>
  75 </tr>
  76 <tr><td align="left" valign="top"><p>
  77               The <a class="link" href="../../../advanced/customize/assign_to.html" title="Store a Parsed Attribute Value (Qi)"><code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">assign_to</span></code></a> customization point
  78               may end up using <a class="link" href="../../../advanced/customize/store_value/push_back.html" title="Store a Parsed Attribute Value into a Container (Qi)"><code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">push_back_container</span></code></a> to assign
  79               the temporary object to the supplied attribute by default, depending
  80               on the types involved. Use the interface described in <a class="link" href="../../../advanced/customize.html" title="Customization of Spirit's Attribute Handling">Customization
  81               of Attribute Handling</a> to manipulate the semantics of this assignment
  82               operation.
  83             </p></td></tr>
  84 </table></div>
  85 <h6>
  86 <a name="spirit.qi.reference.directive.as.h1"></a>
  87             <span><a name="spirit.qi.reference.directive.as.header"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.header">Header</a>
  88           </h6>
  89 <pre class="programlisting"><span class="comment">// forwards to &lt;boost/spirit/home/qi/directive/as.hpp&gt;</span>
  90 <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">qi_as</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
  91 </pre>
  92 <p>
  93             Also, see <a class="link" href="../../../structure/include.html" title="Include">Include Structure</a>.
  94           </p>
  95 <h6>
  96 <a name="spirit.qi.reference.directive.as.h2"></a>
  97             <span><a name="spirit.qi.reference.directive.as.namespace"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.namespace">Namespace</a>
  98           </h6>
  99 <div class="informaltable"><table class="table">
 100 <colgroup><col></colgroup>
 101 <thead><tr><th>
 102                     <p>
 103                       Name
 104                     </p>
 105                   </th></tr></thead>
 106 <tbody>
 107 <tr><td>
 108                     <p>
 109                       <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">as</span> <span class="comment">// alias:
 110                       boost::spirit::qi::as</span></code>
 111                     </p>
 112                   </td></tr>
 113 <tr><td>
 114                     <p>
 115                       <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">as_string</span> <span class="comment">//
 116                       alias: boost::spirit::qi::as_string</span></code>
 117                     </p>
 118                   </td></tr>
 119 <tr><td>
 120                     <p>
 121                       <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">as_wstring</span> <span class="comment">//
 122                       alias: boost::spirit::qi::as_wstring</span></code>
 123                     </p>
 124                   </td></tr>
 125 </tbody>
 126 </table></div>
 127 <h6>
 128 <a name="spirit.qi.reference.directive.as.h3"></a>
 129             <span><a name="spirit.qi.reference.directive.as.synopsis"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.synopsis">Synopsis</a>
 130           </h6>
 131 <pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span>
 132 <span class="keyword">struct</span> <span class="identifier">as</span><span class="special">;</span>
 133 </pre>
 134 <h6>
 135 <a name="spirit.qi.reference.directive.as.h4"></a>
 136             <span><a name="spirit.qi.reference.directive.as.template_parameters"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.template_parameters">Template
 137             parameters</a>
 138           </h6>
 139 <div class="informaltable"><table class="table">
 140 <colgroup>
 141 <col>
 142 <col>
 143 </colgroup>
 144 <thead><tr>
 145 <th>
 146                     <p>
 147                       Parameter
 148                     </p>
 149                   </th>
 150 <th>
 151                     <p>
 152                       Description
 153                     </p>
 154                   </th>
 155 <th>
 156                     <p>
 157                       Default
 158                     </p>
 159                   </th>
 160 </tr></thead>
 161 <tbody><tr>
 162 <td>
 163                     <p>
 164                       <code class="computeroutput"><span class="identifier">T</span></code>
 165                     </p>
 166                   </td>
 167 <td>
 168                     <p>
 169                       A container type. [none
 170                     </p>
 171                   </td>
 172 </tr></tbody>
 173 </table></div>
 174 <h6>
 175 <a name="spirit.qi.reference.directive.as.h5"></a>
 176             <span><a name="spirit.qi.reference.directive.as.model_of"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.model_of">Model
 177             of</a>
 178           </h6>
 179 <div class="blockquote"><blockquote class="blockquote"><p>
 180               <a class="link" href="../parser_concepts/unaryparser.html" title="UnaryParser"><code class="computeroutput"><span class="identifier">UnaryParser</span></code></a>
 181             </p></blockquote></div>
 182 <div class="variablelist">
 183 <p class="title"><b>Notation</b></p>
 184 <dl>
 185 <dt><span class="term"><code class="computeroutput"><span class="identifier">a</span></code></span></dt>
 186 <dd><p>
 187                   A <a class="link" href="../parser_concepts/parser.html" title="Parser"><code class="computeroutput"><span class="identifier">Parser</span></code></a>.
 188                 </p></dd>
 189 <dt><span class="term"><code class="computeroutput"><span class="identifier">t</span></code></span></dt>
 190 <dd><p>
 191                   A container of type <code class="computeroutput"><span class="identifier">T</span></code>.
 192                 </p></dd>
 193 <dt><span class="term"><code class="computeroutput"><span class="identifier">attr</span></code></span></dt>
 194 <dd><p>
 195                   The attribute supplied to the directive.
 196                 </p></dd>
 197 </dl>
 198 </div>
 199 <h6>
 200 <a name="spirit.qi.reference.directive.as.h6"></a>
 201             <span><a name="spirit.qi.reference.directive.as.expression_semantics"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.expression_semantics">Expression
 202             Semantics</a>
 203           </h6>
 204 <p>
 205             Semantics of an expression is defined only where it differs from, or
 206             is not defined in <a class="link" href="../parser_concepts/unaryparser.html" title="UnaryParser"><code class="computeroutput"><span class="identifier">UnaryParser</span></code></a>.
 207           </p>
 208 <div class="informaltable"><table class="table">
 209 <colgroup>
 210 <col>
 211 <col>
 212 </colgroup>
 213 <thead><tr>
 214 <th>
 215                     <p>
 216                       Expression
 217                     </p>
 218                   </th>
 219 <th>
 220                     <p>
 221                       Semantics
 222                     </p>
 223                   </th>
 224 </tr></thead>
 225 <tbody>
 226 <tr>
 227 <td>
 228                     <p>
 229                       <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;()[</span><span class="identifier">a</span><span class="special">]</span></code>
 230                     </p>
 231                   </td>
 232 <td>
 233                     <p>
 234                       Create a temporary object of <code class="computeroutput"><span class="identifier">t</span></code>
 235                       of type <code class="computeroutput"><span class="identifier">T</span></code>,
 236                       and invoke the subject parser <code class="computeroutput"><span class="identifier">a</span></code>,
 237                       supplying <code class="computeroutput"><span class="identifier">t</span></code>
 238                       as an attribute. If the subject parser passes, assign <code class="computeroutput"><span class="identifier">t</span></code> to <code class="computeroutput"><span class="identifier">attr</span></code>.
 239                     </p>
 240                   </td>
 241 </tr>
 242 <tr>
 243 <td>
 244                     <p>
 245                       <code class="computeroutput"><span class="identifier">as_string</span><span class="special">[</span><span class="identifier">a</span><span class="special">]</span></code>
 246                     </p>
 247                   </td>
 248 <td>
 249                     <p>
 250                       Equivalent to <code class="computeroutput"><span class="identifier">as</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">a</span><span class="special">]</span></code>
 251                     </p>
 252                   </td>
 253 </tr>
 254 <tr>
 255 <td>
 256                     <p>
 257                       <code class="computeroutput"><span class="identifier">as_wstring</span><span class="special">[</span><span class="identifier">a</span><span class="special">]</span></code>
 258                     </p>
 259                   </td>
 260 <td>
 261                     <p>
 262                       Equivalent to <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">wstring</span><span class="special">&gt;()[</span><span class="identifier">a</span><span class="special">]</span></code>
 263                     </p>
 264                   </td>
 265 </tr>
 266 </tbody>
 267 </table></div>
 268 <h6>
 269 <a name="spirit.qi.reference.directive.as.h7"></a>
 270             <span><a name="spirit.qi.reference.directive.as.attributes"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.attributes">Attributes</a>
 271           </h6>
 272 <p>
 273             See <a class="link" href="../../quick_reference/compound_attribute_rules.html#spirit.qi.quick_reference.compound_attribute_rules.notation">Compound
 274             Attribute Notation</a>.
 275           </p>
 276 <div class="informaltable"><table class="table">
 277 <colgroup>
 278 <col>
 279 <col>
 280 </colgroup>
 281 <thead><tr>
 282 <th>
 283                     <p>
 284                       Expression
 285                     </p>
 286                   </th>
 287 <th>
 288                     <p>
 289                       Attribute
 290                     </p>
 291                   </th>
 292 </tr></thead>
 293 <tbody><tr>
 294 <td>
 295                     <p>
 296                       <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;()[</span><span class="identifier">a</span><span class="special">]</span></code>
 297                     </p>
 298                   </td>
 299 <td>
 300                     <p>
 301                       <code class="computeroutput"><span class="identifier">a</span><span class="special">:</span>
 302                       <span class="identifier">A</span> <span class="special">--&gt;</span>
 303                       <span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;()[</span><span class="identifier">a</span><span class="special">]:</span>
 304                       <span class="identifier">T</span></code>
 305                     </p>
 306                   </td>
 307 </tr></tbody>
 308 </table></div>
 309 <h6>
 310 <a name="spirit.qi.reference.directive.as.h8"></a>
 311             <span><a name="spirit.qi.reference.directive.as.complexity"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.complexity">Complexity</a>
 312           </h6>
 313 <div class="blockquote"><blockquote class="blockquote"><p>
 314               The complexity is defined by the complexity of the subject parser,
 315               <code class="computeroutput"><span class="identifier">a</span></code>, and the complexity
 316               of the assignment of the container <code class="computeroutput"><span class="identifier">t</span></code>
 317               to the supplied attribute <code class="computeroutput"><span class="identifier">attr</span></code>.
 318             </p></blockquote></div>
 319 <h6>
 320 <a name="spirit.qi.reference.directive.as.h9"></a>
 321             <span><a name="spirit.qi.reference.directive.as.example"></a></span><a class="link" href="as.html#spirit.qi.reference.directive.as.example">Example</a>
 322           </h6>
 323 <div class="note"><table border="0" summary="Note">
 324 <tr>
 325 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td>
 326 <th align="left">Note</th>
 327 </tr>
 328 <tr><td align="left" valign="top"><p>
 329               The test harness for the example(s) below is presented in the <a class="link" href="../basics.html#spirit.qi.reference.basics.examples">Basics Examples</a>
 330               section.
 331             </p></td></tr>
 332 </table></div>
 333 <p>
 334             Some using declarations:
 335           </p>
 336 <p>
 337 </p>
 338 <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">utree</span><span class="special">;</span>
 339 <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">utree_type</span><span class="special">;</span>
 340 <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">utf8_symbol_type</span><span class="special">;</span>
 341 <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">as</span><span class="special">;</span>
 342 <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">as_string</span><span class="special">;</span>
 343 <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">char_</span><span class="special">;</span>
 344 </pre>
 345 <p>
 346           </p>
 347 <p>
 348             Simple usage of <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>,
 349             <code class="computeroutput"><span class="identifier">as_string</span></code> and <code class="computeroutput"><span class="identifier">as_wstring</span></code>:
 350           </p>
 351 <p>
 352             To properly handle string concatenation with <a class="link" href="../../../support/utree.html" title="The utree data structure"><code class="computeroutput"><span class="identifier">utree</span></code></a>, we make use of <code class="computeroutput"><span class="identifier">as_string</span><span class="special">[]</span></code>.
 353             We also use <code class="computeroutput"><span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
 354             to explicitly create a <a class="link" href="../../../support/utree.html" title="The utree data structure"><code class="computeroutput"><span class="identifier">utree</span></code></a> symbol node.
 355           </p>
 356 <p>
 357 </p>
 358 <pre class="programlisting"><span class="identifier">utree</span> <span class="identifier">ut</span><span class="special">;</span>
 359
 360 <span class="keyword">typedef</span> <span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">utf8_symbol_type</span><span class="special">&gt;</span> <span class="identifier">as_symbol_type</span><span class="special">;</span>
 361 <span class="identifier">as_symbol_type</span> <span class="keyword">const</span> <span class="identifier">as_symbol</span> <span class="special">=</span> <span class="identifier">as_symbol_type</span><span class="special">();</span>
 362
 363 <span class="identifier">test_parser_attr</span><span class="special">(</span><span class="string">"foo"</span><span class="special">,</span> <span class="identifier">as_string</span><span class="special">[*</span><span class="identifier">char_</span><span class="special">],</span> <span class="identifier">ut</span><span class="special">);</span>
 364 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">ut</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="comment">// will output &gt;"foo"&lt;</span>
 365 <span class="identifier">BOOST_ASSERT</span><span class="special">(</span><span class="identifier">ut</span><span class="special">.</span><span class="identifier">which</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">utree_type</span><span class="special">::</span><span class="identifier">string_type</span><span class="special">);</span>
 366 <span class="identifier">ut</span><span class="special">.</span><span class="identifier">clear</span><span class="special">();</span>
 367
 368 <span class="identifier">test_parser_attr</span><span class="special">(</span><span class="string">"foo"</span><span class="special">,</span> <span class="identifier">as</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">char_</span><span class="special">],</span> <span class="identifier">ut</span><span class="special">);</span>
 369 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">ut</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="comment">// will output &gt;"foo"&lt;</span>
 370 <span class="identifier">BOOST_ASSERT</span><span class="special">(</span><span class="identifier">ut</span><span class="special">.</span><span class="identifier">which</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">utree_type</span><span class="special">::</span><span class="identifier">string_type</span><span class="special">);</span>
 371 <span class="identifier">ut</span><span class="special">.</span><span class="identifier">clear</span><span class="special">();</span>
 372
 373 <span class="identifier">test_parser_attr</span><span class="special">(</span><span class="string">"foo"</span><span class="special">,</span> <span class="identifier">as_symbol</span><span class="special">[*</span><span class="identifier">char_</span><span class="special">],</span> <span class="identifier">ut</span><span class="special">);</span>
 374 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">ut</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="comment">// will output &gt;foo&lt;</span>
 375 <span class="identifier">BOOST_ASSERT</span><span class="special">(</span><span class="identifier">ut</span><span class="special">.</span><span class="identifier">which</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">utree_type</span><span class="special">::</span><span class="identifier">symbol_type</span><span class="special">);</span>
 376 <span class="identifier">ut</span><span class="special">.</span><span class="identifier">clear</span><span class="special">();</span>
 377
 378 <span class="identifier">test_parser_attr</span><span class="special">(</span><span class="string">"foo"</span><span class="special">,</span> <span class="identifier">as</span><span class="special">&lt;</span><span class="identifier">utf8_symbol_type</span><span class="special">&gt;()[*</span><span class="identifier">char_</span><span class="special">],</span> <span class="identifier">ut</span><span class="special">);</span>
 379 <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">ut</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="comment">// will output &gt;foo&lt;</span>
 380 <span class="identifier">BOOST_ASSERT</span><span class="special">(</span><span class="identifier">ut</span><span class="special">.</span><span class="identifier">which</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">utree_type</span><span class="special">::</span><span class="identifier">symbol_type</span><span class="special">);</span>
 381 </pre>
 382 <p>
 383           </p>
 384 </div>
 385 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 386 <td align="left"></td>
 387 <td align="right"><div class="copyright-footer">Copyright &#169; 2001-2011 Joel de Guzman, Hartmut Kaiser<p>
 388         Distributed under the Boost Software License, Version 1.0. (See accompanying
 389         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>)
 390       </p>
 391 </div></td>
 392 </tr></table>
 393 <hr>
 394 <div class="spirit-nav">
 395 <a accesskey="p" href="hold.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../directive.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="../nonterminal.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a>
 396 </div>
 397 </body>
 398 </html>