Re: Localized precedence declarations

[Akim Demaille]

Le 23 juin 09 à 20:18, Akim Demaille a écrit :

> Le 21 juin 09 à 22:46, Michiel Helvensteijn a écrit :
>
> > It's now 6 years and a bit later. Has this problem been solved in  
> > Bison in the
> > mean time? Because I can not even find a mention of this in the  
> > manual.
>
> Not, it has not been solved, and that is still a todo.  But there  
> are currently many on-going changes in Bison, it is unlikely that we  
> will find time to scope precedence/associativity declarations in the  
> short term.  Contributions are most welcome :)

I should have pointed out two changes that might help you:

- %no-default-prec disables the automatic assignment of a default  
precedence to rules.  This is a nice feature, and I don't understand  
today what I had cold feet about it.  The feature is available in  
shipped Bison, it is just not documented.  See http://lists.gnu.org/archive/html/bison-patches/2003-05/msg00014.html 
 for instance.

We should reenable it.  I.e., we should revert  
91d2c560a84bd5ca4b43f235201b1a04348cd83d.

- there is a new %precedence directive that allows completes %right,  
%left and %nonassoc: it defines only a precedence level, and leaves  
undecided associativity matters.  This is not released, it will be in  
Bison 2.6.  See http://lists.gnu.org/archive/html/bison-patches/2008-11/msg00125.html

A tarball of the master branch of bison is available in 
http://www.lrde.epita.fr/~akim/download/