Allow `float("inf")` and `float("-inf")` in literals

I have been frequently using positive and negative infinity as default values for values that should otherwise be ints. Because of Python's duck typing this is a convenient pattern that sometimes allows reducing some special-casing logic.

def less_than(value: int, limit: int | None) -> bool:
    if limit is None:
        return True
    return value < limit

vs

def less_than(value: int, limit: int | Literal[float("inf")]) -> bool:
    return value < limit

Would it be feasible to special-case the expressions float("inf") and float("-inf") and make type-checkers regard them as literal values, even though they aren't strictly speaking language-level literals?

For posterity, PEP 586 mentions this with:

Representing Literals of infinity or NaN in a clean way is tricky; real-world APIs are unlikely to vary their behavior based on a float parameter.

So I guess what I'm asking here is: am I an odd duckling or could it be worth considering +/- infinity as legal values in literal types?

まず、無効な Literal パラメーターに関する PEP 586 の議論と、この issue にある 21 件のコメントを読んでください。float("inf") と float("-inf") をリテラル値として扱うことについて、typing コミュニティで結論に達しているかどうかを判断してください。完了とするには、合意された仕様と、必要な type-checker の変更が特定されている必要がありますが、この issue にはそれらがありません。