Garrett Goebel <[EMAIL PROTECTED]> writes:
>From: Nick Ing-Simmons [mailto:[EMAIL PROTECTED]]
>> 
>> In order to make that work you have required the lexer to 
>> pass you the {space}markers. That makes the parser do a lot
>> more work throwing them away.
>> 
>> It can also easily stop grammar being LALR(1) and hence yacc/bison
>> parsable - you burn off your one "look ahead" token with the space.
>
>There are a lot of interesting parser/lex/grammar/compiler documentation
>links available at the ANTLR (an LL(k) parser) pages:
>http://www.antlr.org/links.html A good overview of ANTLR itself and other
>topical links can be found at:
>http://www.bearcave.com/software/antlr/antlr_expr.html

The latter has this:

"
LR(k) for any k, most grammars that are not LR(1) are ambigious so the additional 
lookahead doesn't really do what most people think. 

     ANTLR's syntactic predicates allow arbitrary lookahead which can be a powerful 
way to resolve difficult parts of a syntax. But sadly they don't make grammars that
     much easier to develop. ANTLR grammars still take a lot of work and good grammar 
development is an art. 
"
-- 
Nick Ing-Simmons

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