Path: utzoo!yunexus!geac!syntron!jtsv16!uunet!seismo!sundc!pitstop!sun!decwrl!labrea!rutgers!bellcore!clyde!watmath!watdragon!gvcormack
From: gvcormack@watdragon.waterloo.edu (Gordon V. Cormack)
Newsgroups: comp.lang.misc
Subject: Re: Syntactical defininition of English
Message-ID: <9309@watdragon.waterloo.edu>
Date: 26 Oct 88 02:53:17 GMT
Article-I.D.: watdrago.9309
References: <726@wsccs.UUCP> <44600003@hcx2>
Organization: U of Waterloo, Ontario
Lines: 36

In article <44600003@hcx2>, dougs@hcx2.SSD.HARRIS.COM writes:
> is either too exhaustive to be useful or just simply beyond a CFL.  Hey, if
> a context-free grammer can't recognize the regular expression
> 
>               x  y  z  y  x     (note: this requires a pushdown machine with
> 	     a  b  c  b  a             multiple stacks, more power than an 
> 				       automata equivalent to a CFL can be)
> 


1.  the expression above is not regular
2.  the expression above is easily expressed as a CFG:

     A -> B
     A -> a A a
     B -> C
     B -> b B b
     C ->
     C -> C c

3.  two stacks suffice for most recognition problems
4.  grammer [sic] is misspelled
5.  automata is plural
6.  why is everybody picking on this guy so much?  All he asked
    for was a CFG for English.  If I asked for a CFG for Pascal,
    would you hassle me about all the Pascal constructs that aren't
    context-free?
7.  The UNIX command "style" contains a yacc grammar for English.
    A paper is included in the supplementary UNIX documentation
    describing "style", but the source is not supplied with the
    BSD distribution.
-- 
Gordon V. Cormack     CS Dept, University of Waterloo, Canada N2L 3G1
                      gvcormack@waterloo  { .CSNET or .CDN or .EDU }
                      gvcormack@uwaterloo.CA
                      gvcormack@water         { UUCP or BITNET }