Re: passing down value of terminal

[Hans Aberg]

On 22 Nov 2006, at 19:41, vlad florentino wrote:

> In gnu bison:
>
> I have a couple of productions of this type:
> ID '.' complex
>  : {...}
>  ;
>
> complex
>  : FOOBAR  {...}
>  ;
>
> How can I pass the value of ID, a terminal, down to the production
> 'complex', a non terminal. I would like to determine what's the  
> value of ID
> and take actions based on that, i.e.:
>  complex
>  : FOOBAR
>  {
>    if( strcmp(ID.value,"this") == 0)
>      doThis();
>    else
>      doThat();
>   }

You can't within the parser itself, as it is a bottom-up parser; so  
some trick is needed. So either use variable global to the parser, or  
write it in the action of the first rule you have above (using $1).  
You might also attempt using negative $k numbers (perhaps $-1 in your  
case), but that is tricky: for one, thing, it will break if you  
variable "complex" is used in some other context.

  Hans Aberg