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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>}




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