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Next: <a href="Pure-Calling.html#Pure-Calling" accesskey="n" rel="next">Pure Calling</a>, Previous: <a href="Token-Values.html#Token-Values" accesskey="p" rel="prev">Token Values</a>, Up: <a href="Lexical.html#Lexical" accesskey="u" rel="up">Lexical</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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<a name="Textual-Locations-of-Tokens"></a>
<h4 class="subsection">4.6.3 Textual Locations of Tokens</h4>

<a name="index-yylloc-4"></a>
<p>If you are using the &lsquo;<samp>@<var>n</var></samp>&rsquo;-feature (see <a href="Tracking-Locations.html#Tracking-Locations">Tracking Locations</a>)
in actions to keep track of the textual locations of tokens and groupings,
then you must provide this information in <code>yylex</code>.  The function
<code>yyparse</code> expects to find the textual location of a token just parsed
in the global variable <code>yylloc</code>.  So <code>yylex</code> must store the proper
data in that variable.
</p>
<p>By default, the value of <code>yylloc</code> is a structure and you need only
initialize the members that are going to be used by the actions.  The
four members are called <code>first_line</code>, <code>first_column</code>,
<code>last_line</code> and <code>last_column</code>.  Note that the use of this
feature makes the parser noticeably slower.
</p>
<a name="index-YYLTYPE-1"></a>
<p>The data type of <code>yylloc</code> has the name <code>YYLTYPE</code>.
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bison-doc 1:3.0.2-1 / usr / share / doc / bison-doc / html / Token-Locations.html
