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<h3 class="unnumberedsec">ERASEME55</h3>
<div class="example">
<pre class="verbatim">To: Colin Paul Adams &lt;colin@colina.demon.co.uk&gt;
Subject: Re: Flex C++ classes and Bison
In-reply-to: Your message of 09 Aug 1997 17:11:41 PDT.
Date: Fri, 15 Aug 1997 10:48:19 PDT
From: Vern Paxson &lt;vern&gt;

&gt; #define YY_DECL   int yylex (YYSTYPE *lvalp, struct parser_control
&gt; *parm)
&gt;
&gt; I have been trying  to get this to work as a C++ scanner, but it does
&gt; not appear to be possible (warning that it matches no declarations in
&gt; yyFlexLexer, or something like that).
&gt;
&gt; Is this supposed to be possible, or is it being worked on (I DID
&gt; notice the comment that scanner classes are still experimental, so I'm
&gt; not too hopeful)?

What you need to do is derive a subclass from yyFlexLexer that provides
the above yylex() method, squirrels away lvalp and parm into member
variables, and then invokes yyFlexLexer::yylex() to do the regular scanning.

		Vern
</pre></div>




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flex-doc 2.6.4-6 / usr / share / doc / flex-doc / html / ERASEME55.html
