On Fri, 24 Nov 2006, Joel E. Denny wrote: > > OK, how about this idea? If rules use the syntax S$A to mean that the > > symbol S has a value that can be called $A within an action, then > > let's use plain S to mean the symbol doesn't have a value. > > What about default names?
Another problem is that all existing grammars would implicitly declare all
values to be unused even when they're not. For example:
exp: exp '+' exp { $$ = $1; } ;
There's no warning about $3.
