from typing import Callable, Any

class tailRecursion:
    """Tail-call optimization wrapper."""

    f: Callable[..., Any]
    args: tuple[Any, ...]
    kwargs: dict[str, Any]

    def __init__(self, func: Callable[..., Any], *args: Any, **kwargs: Any) -> None:
        self.f: Callable[..., Any] = func
        self.args: tuple[Any, ...] = args
        self.kwargs: dict[str, Any] = kwargs

    def __call__(self) -> Any:
        return self.f(*self.args, **self.kwargs)

    @staticmethod
    def eval(val: Any) -> Any:
        """Evaluate tail calls recursively until completion."""
        while isinstance(val, tailRecursion):
            val = val()
        return val