Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!sun-barr!decwrl!megatest!djones
From: djones@megatest.UUCP (Dave Jones)
Newsgroups: comp.lang.c
Subject: Re: precedence of && (was: precedence of ?:)
Message-ID: <8068@goofy.megatest.UUCP>
Date: 15 Sep 89 01:59:30 GMT
References: <1989Sep14.181049.8175@twwells.com)
Organization: Megatest Corporation, San Jose, Ca
Lines: 20

From article <1989Sep14.181049.8175@twwells.com), by bill@twwells.com (T. William Wells):

) 
) : (If I ever write a C compiler, I'm going to use precedence, and if
) : anybody ever complains that they got an "L-value" error message when they
) : distinctly asked for a "syntax" error message, maybe I'll offer to wash
) : their car.)
) 
) I wrote a precedence parser for C expressions. It was a mass of
) kludges on top of fudges. I threw it away. C is just not specifiable
) by precedence.
) 

You misunderstand my intensions. I agree that precedence parsers are
obsolete.  By "use precedence"  I just refer to disambiguation rules
such as the yacc %left and %prec directives. They make life easy and
LR tables short. Take a peek a the cgram.y file in the source of the
so called "portable" C compiler, if you dare. It may not be pretty,
but it would be even not prettier if it were not for the precedence
rules.