[antlr-interest] Clarification on Attribute Reference in Actions

[Kay Roepke]

On Jul 5, 2007, at 1:40 PM, Gavin Lambert wrote:

> At 11:22 5/07/2007, Kay Roepke wrote:
> >term returns [Term t]
> >	:	^(ComplexTerm term termSequence)
> >	{
> >		Object o = asObject($term.t);
> >	}
> >	;
> [...]
> >Notice how it references retval.t in my version. I think
> >this is a bug in the actionparser code. It should warn
> >you that $term.t will refer to the rule's return
> >value and not the subtree reference's retval object.
>
> I don't know, the current behaviour makes a certain amount of sense  
> to me.  If the action block was inside the parentheses, though, I'd  
> definitely expect it to refer to the recursive term, and not the  
> parent rule.

Definitely. What I was proposing was that it merely warns you of the  
ambiguity, it should still pick the return value. However, if you  
meant the rule reference `term` ANTLR should tell you what to do.
It was only about the warning, not about changing the behavior.

cheers,
-k

-- 
Kay Röpke
http://classdump.org/