[antlr-interest] parse tree construction
Sam Barnett-Cormack
s.barnett-cormack at lancaster.ac.uk
Tue Aug 25 09:27:00 PDT 2009
Safiye Celik wrote:
> Hi
> I wanna ask one more question about parse tree construction..
> I have such a rule:
>
> x: A B (C A B)* and I have to create such a tree for it:
>
>
> B
> / | \
> A C B
> / | \
> A C B
> / | \
> A..C. B......and
> continues like that. (The leftmost a B is in the rule, the closest it is
> to the root of the tree.This is true also for other tokens)
>
> How can I create such a tree for that rule? the "*" confuses everything :(
I *believe* (I may be wrong) that you need to formulate the rule using
recursion, rather than EBNF. While (tail-)recursion and EBNF are
equivalent in matching, they produce different results in tree
constructions. I could very well be wrong, of course.
--
Sam Barnett-Cormack
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