refactor(grammar): modernize string formatting with f-strings and improve type hinting

[ardozcnn]

Replaced legacy % string formatting across Symbol, Terminal, RuleOptions, and Rule classes with modern Python f-strings.

Added missing type hints for method parameters (other: Any, memo: Optional[Dict], f: Callable) and return types (-> None, -> str, -> int).

Included empty_indices in RuleOptions.repr to accurately reflect all initialization parameters.

Formatted tuple entries in serialize_fields consistently.

[erezsh]

Overall looks okay. You can use tox to run the type checker with the official configuration.

[ardozcnn]

changed

[ardozcnn]

I ran the code can you check?

[erezsh]

Opus says (and I agree):

1. NonTerminal.serialize — the memo hint is wrong. memo is never a dict; it's a SerializeMemoizer (see Serialize.memo_serialize, and _serialize in utils.py, which already types it that way). mypy doesn't catch it because the base method leaves memo implicitly Any. Please use Optional[SerializeMemoizer], or Any to match lalr_parser.py.

2. renamed should return Self, not Symbol. The body is type(self)(...), so NonTerminal.renamed() returns a NonTerminal. Annotating it Symbol makes correct code fail to typecheck — e.g. rule.origin = rule.origin.renamed(f) errors with "expression has type Symbol, variable has type NonTerminal". It slips through today only because the single caller (load_grammar.py:1053) is in an untyped context.

We support Python 3.8 and have no runtime dependencies, so import it the way common.py already does:

if TYPE_CHECKING:
if sys.version_info >= (3, 11):
from typing import Self
else:
from typing_extensions import Self

[ardozcnn]

Thanks for the detailed review! I've updated renamed() to return Self (handled via TYPE_CHECKING for Python 3.8 compatibility) and changed memo in NonTerminal.serialize to Any as suggested.

[erezsh]

You accidentally deleted the ###} comments that are needed for the standalone parser.

[ardozcnn]

Sorry about that! I've restored the ###} comment for the standalone parser. Thanks for the review