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From: Micha <micha-1@fantasymail.de>
To: caml-list@yquem.inria.fr
Subject: Re: [Caml-list] The lexer hack
Date: Sat, 14 Nov 2009 17:20:13 +0100
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Cc: Dario Teixeira <darioteixeira@yahoo.com>
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X-Spam: no; 0.00; lexer:01 parser:01 lexers:01 parser:01 lexing:01 lexer:01 compiler:01 tokens:01 10.:98 2009:98 wrote:01 parsing:01 caml-list:01 grammar:02 hack:04 

On Tuesday, 10. November 2009 15:42:52 Dario Teixeira wrote:
> Hi,
>
> I'm creating a parser for a LaTeX-ish language that features verbatim
> blocks. To handle them I want to switch lexers on-the-fly, depending on the
> parsing context.  Therefore, I need the state from the (Menhir generated)
> parser to influence the lexing process (I believe this is called the "lexer
> hack" in compiler lore).

if the lexer cannot decide it on the tokens seen, a packrat parser (like 
Aurochs) may be a better choice, since in a PEG there is no seperate lexer, 
it's all one grammar, so you don't have this problem.

 Michael