[antlr-interest] Can't see the wood (@init and @after)

[Paul Keir]

Thanks for the explanation Jim, although I still have trouble putting 
the conclusions it into practise. I remain confused about @init's safe use.

Can I suggest that as a simple rule-of-thumb for beginners, that @init 
should be avoided, except when used to declare rule-local variables?

I'm now hoping that I can at least continue to use @after. I don't seem 
to have the same problems when I use @after, and a variant (below) of my 
a/b test for it, safely returns an equal number of a and b characters.

expression
@after { System.out.println("a"); }
    : assignment_expression (',' assignment_expression)*
    { System.out.println(" b"); }
    ;

Cheers,
Paul