Re: [Boost-Users] Question about SPirit parser terminology

From: Joel de Guzman (djowel_at_[hidden])
Date: 2003-04-14 18:06:40

satya_vajja wrote:
> Can anyone explain me what is the difference between a rule, grammar
> and parser in SPIRIT parser library.

A grammar is a set of rules. Rules and grammars when instantiated,
create immediately runnable parsers. Often times, rules and grammars
are called parsers simply because rules and grammars *are* parsers, in
the inheritance point of view (they inherit from the abstract parser
base class). Schematically:

        parser
        /    \
     rule   grammar
     
    grammar
    {
        rule a;
        rule b;
        rule c;
        rule start;
    };

HTH,
-- 
Joel de Guzman
joel at boost-consulting.com
http://www.boost-consulting.com
http://spirit.sf.net