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From: pg@bsg.com (Peter Garst)
Newsgroups: comp.compilers
Subject: Parsing one sentence at a time
Keywords: yacc, debug, ydb
Message-ID: <1991Mar19.160026.10471@iecc.cambridge.ma.us>
Date: 18 Mar 91 19:18:42 GMT
References: <1991Mar15.164557.12439@infonode.ingr.com>
Sender: compilers-sender@iecc.cambridge.ma.us
Reply-To: pg@bsg.com (Peter Garst)
Organization: Compilers Central
Lines: 17
Approved: compilers@iecc.cambridge.ma.us

Thomas Vaught asks:

>   Is there a way in which I can use yacc to parse a grammar
>   one sentence, a production which makes up a sentence, at a time?

Our product, ydb, is a 100% backward compatible upgrade to yacc which
does this, among other things. You can call return from any action,
and continue the parse by calling yyparse() again. For example, we
did a C preprocessor this way; each time you call yyparse() it returns
one token in the input stream.

Peter Garst
P.O. Box 390018, Mountain View CA 94039 USA

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