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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.programming
Subject: Re: My answer about Ada and FreePascal and C++
Date: Fri, 01 Jan 2016 14:34:35 +0000
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JJ <jj4public@vfemail.net> writes:

> On Fri, 1 Jan 2016 01:07:16 +0000 (UTC), Kaz Kylheku wrote:
>> 
>> See this Pascal BNF grammar, for instance, which looks like
>> some traditiona, old Pascal:
>> 
>> http://www2.informatik.uni-halle.de/lehre/pascal/sprache/pas_bnf.html
>> 
>> In every production where a semicolon terminal symbol appears, it is
>> preceded and followed by something (a something which doesn't derive
>> an empty string). Hence it is a separator.
>
> As far as I can see, it's a flaw in the Backus–Naur Form itself. Backus–Naur
> Form doesn't require a terminator character at the end of each rule.

No, there's nothing wrong with BNF itself.  It can describe a language where
a semicolon is a statement separator:

  statement-list:
     statement
     statement-list ; statement

and it can describe one in which the semicolon is a statement
terminator:

  statement-list:
     statement ;
     statement-list statement ;

although in the later case it's more normal to put the semicolon into
the production for a statement:

  statement-list:
     statement
     statement-list statement
   
  statement:
     statement-content ;

<snip>
-- 
Ben.