On Wed, 8 Aug 2007, Hans Aberg wrote: > On 8 Aug 2007, at 14:20, Laurence Finston wrote: > > The Bison from the CVS works fine, too. :-) >
That's a good idea, thanks. I didn't think of doing that. As long as I had to install it locally, I might as well keep up with the development versions. > >It would be nice to know exactly what makes Bison abort. I suspect it has > >to do with the states, but I wasn't able to understand why it would fail > >in some cases and not in others. > > It can be difficult. Some work has been done in order to extend the old Bison > limits, just in order to enable larger grammars, but I do not know exactly its > state. And only the latest version is developed. So if an older version does > not work, the only option is to switch to the latest, and if that one does not > work, trying to get that one fixed. I'm sure you're right that it's a good idea to try to get rid of the s/r conflicts. I've gotten rid of some rules that follow this pattern: command: message_command message_command: error_message message_command: message Now I've got: command: message command: error_message (These are just examples, the real code was a bit different.) In the one case I checked, getting rid of the entire subcategory of `command', e.g., `message_command' with all of the rules with `message_command' on the left-hand side, got rid of precisely one state, and didn't reduce the number of s/r conflicts at all. I liked having the subcategories of `command' because it made it clearer for a person reading the grammar. I'm now not sure whether it's a problem for Bison or not. However, I don't really feel like putting them all back in again. Anyway, thanks again, and I apologize for not thinking of trying the most recent version before asking. Laurence _______________________________________________ [email protected] http://lists.gnu.org/mailman/listinfo/help-bison
