[antlr-interest] Need some help with AST creation

[Luis Pureza]

Hi,

I need some help from the ANTLR wizards :)

I'm trying to match expressions with field accesses and array indexes.
For example:

costumers.length
costumers[0].address
costumers[costumers.length - 1].orders[0].total


The following rule seems to work:

fieldExpr      : atom ('.'^ identifier | ('['^ expr ']'!))*;

However, it creates trees with notes annotated with '[', and I'd
prefer to have a dummy token like INDEX. For example, costumers[0] now
returns

([ (ID costumers) (INT 0))

But I'd like it to return

(INDEX (ID costumers) (INT 0))

I tried to create the AST manually with -> ^(...), but I ended up
nowhere. Maybe I should've tried to refactor the grammar, but that
would make it a little less readable, so I didn't do it.
How do you suggest I do this?

Thank you!