[antlr-interest] Automatic lists

Ben Corne ben.corne at gmail.com
Tue May 17 06:44:24 PDT 2011


Found it in the definitive antlr guide: adding a ? behind $docs did the
trick.

2011/5/17 Ben Corne <ben.corne at gmail.com>

> Hi
>
> I'm trying to create a rule looking like this:
> ==================================
> statement
>   : ( docs+=documentation )*
>   ( def=definition -> ^(AGSTATEMENT $docs $def)
>  | tdef=typedefinition -> ^(AGSTATEMENT $docs $tdef)
> | imp=imports -> ^(AGSTATEMENT $docs $imp)
>    // TODO: (variable EQL) => varassignment
>    // TODO: (assignment) => assignment
>  | exp=expression -> ^(AGSTATEMENT $exp $docs)
>   ;
> ==================================
>
> This rule should add a bunch of documentation constructs to each type of
> statement. Testing with at least one documentation per statement, everything
> works as expected.
>
> Now the problem is that when I test statements without any documentation
> added to a statement, the ANTLRworks debugger seems to stop after the first
> such statement, refusing to go parse the folowing statements.
>
> I suspect that it is because the $docs variable is never initialized since
> nothing is added. How should I fix this?
>
> Regards
> Ben C.
>


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