Path: utzoo!attcan!uunet!lll-winken!sun-barr!olivea!mintaka!spdcc!esegue!compilers-sender
From: rekers@cwi.nl (Jan Rekers)
Newsgroups: comp.compilers
Subject: Re: Can Pascal be parsed by LR(1) parsing algorithm?
Keywords: pascal, parse, LR(1)
Message-ID: <2365@charon.cwi.nl>
Date: 16 Oct 90 11:01:48 GMT
References: <9010091533.AA02386@apple.com> <9010101445.AA06181@dynamo.ecn.purdue.edu> <1990Oct16.015524.25858@comp.vuw.ac.nz>
Sender: compilers-sender@esegue.segue.boston.ma.us
Reply-To: rekers@cwi.nl (Jan Rekers)
Organization: CWI, Amsterdam
Lines: 19
Approved: compilers@esegue.segue.boston.ma.us

In article <1990Oct16.015524.25858@comp.vuw.ac.nz>,
lindsay@comp.vuw.ac.nz (Lindsay Groves) writes:

|> For example, the following syntax diagram describes the language
|> consisting of all non-empty palindromes of even length over the alphabet
|> {a, b}.  This language is inherently ambiguous (ie cannot be recognised
|> by a deterministic PDA), so it is definitely not LL(1) (nor LL(k),
|> LR(k), ...):

The language of non-empty palindromes is not inherently ambiguous, the
language of _sequences_of_ non-empty palindromes is. The syntax diagram
you provide does describe _sequences_ of palindromes.

Jan Rekers (rekers@cwi.nl)    Centrum voor Wiskunde en Informatica (CWI)
			      P.O. Box 4079, 1009 AB Amsterdam, The Netherlands

-- 
Send compilers articles to compilers@esegue.segue.boston.ma.us
{ima | spdcc | world}!esegue.  Meta-mail to compilers-request@esegue.