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The lexer hack
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Date: 2009-11-14 (19:09)
From: Goswin von Brederlow <goswin-v-b@w...>
Subject: Re: [Caml-list] The lexer hack
Micha <micha-1@fantasymail.de> writes:

> 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

There usualy must be something present to support '(* <vebatim
text> *)' and '"<verbatim text>"', i.e. comments and strings.
Find out what is recommended for those and adapt it.