[antlr-interest] If statement for Tree-based Interpreter: is it the correct way to do it?

[Terence Parr]

On Aug 23, 2007, at 11:02 AM, Pavel Ganelin wrote:

>
> Hi,
>
> I found that in ANTLR v3 it is more difficult to skip the child for  
> tree walker compare with v2. Is it true or it is just learning curve?
>
> Below I attached how I process if statement for a tree-based  
> interpreter. Please note that I had to add artificial token EOL  
> while building the tree in the parser so that I could position the  
> cursor just before Token.UP. I did not find a way to move the  
> pointer to the last node of the the given tree ($s in the example  
> below). Start and Stop indexes in the tree node point to the  
> original token tree, not the CommonTreeNodeStream.
>
> Is it the way it is supposed to be implemented? If not what is the  
> correct approach
>
> PS. I did read  http://www.antlr.org/wiki/display/ANTLR3/Simple 
> +tree-based+interpeter. It does not cover this question.

Hi Pavel,

 From that page:

^(FUNC name=ID arg=ID .)

The dot skips the body subtree :)

Ter