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<a name="Complete-Symbols"></a>
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<p>
Previous: <a href="Split-Symbols.html#Split-Symbols" accesskey="p" rel="prev">Split Symbols</a>, Up: <a href="C_002b_002b-Scanner-Interface.html#C_002b_002b-Scanner-Interface" accesskey="u" rel="up">C++ Scanner Interface</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index-of-Terms.html#Index-of-Terms" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="Complete-Symbols-1"></a>
<h4 class="subsubsection">10.1.5.2 Complete Symbols</h4>

<p>If you specified both <code>%define api.value.type variant</code> and
<code>%define api.token.constructor</code>,
the <code>parser</code> class also defines the class <code>parser::symbol_type</code>
which defines a <em>complete</em> symbol, aggregating its type (i.e., the
traditional value returned by <code>yylex</code>), its semantic value (i.e., the
value passed in <code>yylval</code>, and possibly its location (<code>yylloc</code>).
</p>
<dl>
<dt><a name="index-symbol_005ftype-on-symbol_005ftype"></a>Method on symbol_type: <em></em> <strong>symbol_type</strong> <em>(token_type <var>type</var>,  const semantic_type&amp; <var>value</var>, const location_type&amp; <var>location</var>)</em></dt>
<dd><p>Build a complete terminal symbol which token type is <var>type</var>, and which
semantic value is <var>value</var>.  If location tracking is enabled, also pass
the <var>location</var>.
</p></dd></dl>

<p>This interface is low-level and should not be used for two reasons.  First,
it is inconvenient, as you still have to build the semantic value, which is
a variant, and second, because consistency is not enforced: as with unions,
it is still possible to give an integer as semantic value for a string.
</p>
<p>So for each token type, Bison generates named constructors as follows.
</p>
<dl>
<dt><a name="index-make_005ftoken-on-symbol_005ftype"></a>Method on symbol_type: <em></em> <strong>make_<var>token</var></strong> <em>(const <var>value_type</var>&amp; <var>value</var>, const location_type&amp; <var>location</var>)</em></dt>
<dt><a name="index-make_005ftoken-on-symbol_005ftype-1"></a>Method on symbol_type: <em></em> <strong>make_<var>token</var></strong> <em>(const location_type&amp; <var>location</var>)</em></dt>
<dd><p>Build a complete terminal symbol for the token type <var>token</var> (not
including the <code>api.token.prefix</code>) whose possible semantic value is
<var>value</var> of adequate <var>value_type</var>.  If location tracking is enabled,
also pass the <var>location</var>.
</p></dd></dl>

<p>For instance, given the following declarations:
</p>
<div class="example">
<pre class="example">%define api.token.prefix {TOK_}
%token &lt;std::string&gt; IDENTIFIER;
%token &lt;int&gt; INTEGER;
%token COLON;
</pre></div>

<p>Bison generates the following functions:
</p>
<div class="example">
<pre class="example">symbol_type make_IDENTIFIER(const std::string&amp; v,
                            const location_type&amp; l);
symbol_type make_INTEGER(const int&amp; v,
                         const location_type&amp; loc);
symbol_type make_COLON(const location_type&amp; loc);
</pre></div>

<p>which should be used in a Lex-scanner as follows.
</p>
<div class="example">
<pre class="example">[0-9]+   return yy::parser::make_INTEGER(text_to_int (yytext), loc);
[a-z]+   return yy::parser::make_IDENTIFIER(yytext, loc);
&quot;:&quot;      return yy::parser::make_COLON(loc);
</pre></div>

<p>Tokens that do not have an identifier are not accessible: you cannot simply
use characters such as <code>':'</code>, they must be declared with <code>%token</code>.
</p>
<hr>
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Previous: <a href="Split-Symbols.html#Split-Symbols" accesskey="p" rel="prev">Split Symbols</a>, Up: <a href="C_002b_002b-Scanner-Interface.html#C_002b_002b-Scanner-Interface" accesskey="u" rel="up">C++ Scanner Interface</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index-of-Terms.html#Index-of-Terms" title="Index" rel="index">Index</a>]</p>
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