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From: johnl@haddock.UUCP
Newsgroups: net.unix-wizards
Subject: Re: Re: Comment recognition in Lex, agai - (nf)
Message-ID: <161@haddock.UUCP>
Date: Mon, 7-May-84 23:40:56 EDT
Article-I.D.: haddock.161
Posted: Mon May  7 23:40:56 1984
Date-Received: Thu, 10-May-84 00:28:33 EDT
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#R:watmath:-766600:haddock:16800012:000:685
haddock!johnl    May  7 14:28:00 1984

The problem with recognizing comments as single Lex tokens is that Lex
has a finite sized token buffer.  If your comments are bigger than the
buffer, you lose.

What should work is to put in a COMMENT start state and do this:

"/*"            BEGIN COMMENT;  /* start a comment */

<COMMENT>"*/"   BEGIN 0;        /* return to regular state */

<COMMENT>.|\n   ;               /* throw everything else away */

Unfortunately, I've never had much luck with making lex programs that
include start states work.  Everybody lets lex recognize the /* and
writes C code to eat the comment; if you read the manual page for lex,
you'll find exactly that in the example.

John Levine, ima!johnl