Re: [Caml-list] Re: The lexer hack

[Francois Pottier <Francois.Pottier@inria.fr>]

Hello,

On Tue, Nov 10, 2009 at 08:26:23AM -0800, Dario Teixeira wrote:
> Anyway, I was looking at Dypgen's early actions, and an idea
> occurred to me: I can create dummy empty actions that simply
> change a global "parsing context" variable:
> 
> inline:
>   | (...)
>   | BEGIN_VERB enter_verb RAW END_VERB exit_verb {Ast.Verbatim $3}
>   | (...)
> 
> enter_verb:  /* empty */  {Global.context := Global.Verbatim}
> exit_verb:   /* empty */  {Global.context := Global.General}
> 
> 
> Still hackish, but better than creating a state machine...

Interesting. Have you confirmed that this works? I am slightly worried by the
fact that an LR parser reads one token ahead, i.e. one token past BEGIN_VERB
might already have been read before the enter_verb semantic action is
executed. If that is so, then this token would be read while the lexer is
still in the wrong mode.

-- 
François Pottier
Francois.Pottier@inria.fr
http://gallium.inria.fr/~fpottier/