Discussion List Archives

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Modification to BNF needed for <line_of_text>?

  • Subject: Re: Modification to BNF needed for <line_of_text>?
  • From: Nick Spadaccini <nick@xxxxxxxxxxxxx>
  • Date: Mon, 1 Jul 2002 04:33:56 +0100 (BST)
On Mon, 1 Jul 2002, James Hester wrote:

> the spec to
> 
> <line_of_text> ::= <not_a_semi_colon | terminate> <char>* <terminate>
> 
> or adding <terminate> to <not_a_semi_colon>

Neither of these will work will they(?), because the rules above require
two consecutive <terminate>s to match. 

What you want is


<line_of_text> ::= { <not_a_semi_colon> <char>* | epsilon } <terminate>

epsilon being the empty string or more long winded,

<line_of_text> ::= {<not_a_semi_colon> <char>* <terminate> | <terminate>}

Thoughts?

cheers

Nick

--------------------------------
Dr N. Spadaccini                           Deputy Head of Department

Department of Computer Science &            voice: +(61 8) 9380 3452
Software Engineering                          fax: +(61 8) 9380 1089
University of Western Australia            email: nick@cs.uwa.edu.au            
35 Stirling Highway                      w3: www.cs.uwa.edu.au/~nick
CRAWLEY, Perth,  WA  6009             
AUSTRALIA                               CRICOS Provider Code: 00126G


Reply to: [list | sender only]
International Union of Crystallography

Scientific Union Member of the International Council for Science (admitted 1947). Member of CODATA, the ICSU Committee on Data. Member of ICSTI, the International Council for Scientific and Technical Information. Partner with UNESCO, the United Nations Educational, Scientific and Cultural Organization in the International Year of Crystallography 2014.

ICSU Scientific Freedom Policy

The IUCr observes the basic policy of non-discrimination and affirms the right and freedom of scientists to associate in international scientific activity without regard to such factors as ethnic origin, religion, citizenship, language, political stance, gender, sex or age, in accordance with the Statutes of the International Council for Science.