Re: initial-action question

[Hans Aberg]

On 11 Feb 2008, at 09:17, Aaron Jackson wrote:

> I would like to declare some variables that are local to yyparse.   
> I am building a linked list of structures, and I need to make sure  
> I have values for all the structure members before I add a new node  
> to the list.  Since I wrote the parser to be a pure parser, global  
> variables, are not an option.  Something like %initial-action {int  
> x; int y; int z;} doesn't work, since the initial action code is  
> enclosed in braces and the variables x,y,z,etc. do not exist  
> outside the braces.

If that happens, it is probably a bug.

>   If I use %parse-param{variables_t variables;}, where variables_t  
> is a structure containing x,y,z, I get what I want, but since I  
> don't need x,y,z after yyparse returns, this seems like an  
> inefficient way to do things.  Is there a better way to do this?

There is a command %define or something that lets you defining a M4  
macor that can be put into the skeleton file.

> There must be a "standard" way this is done---temporarily saving  
> all the previously parsed values until all the required values are  
> available.

Not really: the origin is in impure parsers for rather standard  
situations.

  Hans Aberg