Resolve parser choice conflicts by adjusting lookahead in index-related rules

[minleejae]

Hi @manticore-projects,

This PR addresses multiple parser choice conflicts by increasing the LOOKAHEAD values in the index-related grammar rules.

✅ Resolved Warnings:
The following conflicts have been resolved:

Warning: Choice conflict in (...)* construct at line 7661, column 5.
         Expansion nested within construct and expansion following construct
         have common prefixes, one of which is: "WITH"
         Consider using a lookahead of 2 or more for nested expansion.
Warning: Choice conflict involving two expansions at
         line 7860, column 17 and line 7888, column 17 respectively.
         A common prefix is: "SPATIAL" "COMMENT"
         Consider using a lookahead of 3 or more for earlier expansion.

⚠️ Remaining Warnings:
However, the following two warnings still remain:

Warning: Choice conflict in [...] construct at line 7863, column 19.
         Expansion nested within construct and expansion following construct
         have common prefixes, one of which is: "INDEX"
         Consider using a lookahead of 2 or more for nested expansion.
Warning: Choice conflict in [...] construct at line 8363, column 9.
         Expansion nested within construct and expansion following construct
         have common prefixes, one of which is: "WITH"
         Consider using a lookahead of 2 or more for nested expansion.

From what I can tell, these may stem from ambiguities involving Identifier vs keyword-based starts (INDEX, WITH, etc.). I suspect a deeper refactoring of how Identifier and keyword lookahead are handled might be needed.

If there’s a better pattern or common best practice to resolve such nested choice conflicts (especially those involving Identifier vs keyword lookahead), I’d appreciate your advice before going further.

Thanks!

[manticore-projects]

Thanks, I have completed the rest.
Cheers!

[minleejae]

@manticore-projects
Thanks! Learned something new about lookahead!

[manticore-projects]

@manticore-projects Thanks! Learned something new about lookahead!

If you ask me, its rather a shortcoming/problem of JavaCC itself. Your lookaheads were not wrong in my opinion and my syntax should not make any difference.