Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site wivax.UUCP
Path: utzoo!linus!decvax!wivax!mckeeman
From: mckeeman@wivax.UUCP
Newsgroups: net.lang.c
Subject: Re: 2 b larl(a)
Message-ID: <19565@wivax.UUCP>
Date: Wed, 30-May-84 11:42:05 EDT
Article-I.D.: wivax.19565
Posted: Wed May 30 11:42:05 1984
Date-Received: Fri, 1-Jun-84 07:32:15 EDT
Sender: mckeeman@wivax.UUCP
Organization: Wang Institute, Tyngsboro, Ma.  01879
Lines: 26

Following my ``<ident> ::= IF'' suggestion, Brian Thomson writes

>>>Actually, I believe this would fail in most cases, at least for
>>>the IF keyword.  If your grammar contains
>>>
>>>   <statement> ::= IF <expression> THEN ....
>>>   <ident>     ::= IF
>>>
>>>and an <expression> may begin with a left parenthesis
>>>it will fail to be LALR(1) because of the resulting shift-reduce conflict.
>>>'IF (' is a prefix of a valid procedure call.
>>>I don't know of any way to resolve the conflict, do you?
>>>--

Ooops.  You are right.  My constructor (flesh & blood)
fails to handle IF followed by '('.  All readers should
delete my claim until and if I can restate it accurately.
The actual history of my hasty statement is a PL/I subset
where we used this trick to conform to the 'no reserved
word' definition of that language.  It failed only on NOT
as I remember, but now I am unwilling to trust foggy
memories and unable to run a system dead these many years.

/s/ Bill   McKeeman.Wang-Inst at CSNet-Relay
           ...decvax!wivax!mckeeman
           Wang Institute of Graduate Studies, Tyngsboro, MA 01879