相关疑难解决方法(0)

目前，当我无法在函数签名中分配默认参数和/或已经具有含义时，我会使用此策略。None

from typing import Optional

DEFAULT = object()


# `None` already has meaning.
def spam(ham: Optional[list[str]] = DEFAULT):
    if ham is DEFAULT:
        ham = ['prosciutto', 'jamon']
    if ham is None:
        print('Eggs?')
    else:
        print(str(len(ham)) + ' ham(s).')

错误：

Failed (exit code: 1) (2607 ms)

main.py:7: error: Incompatible default for argument "ham" (default has type "object", argument has type "Optional[List[str]]")
Found 1 error in 1 file (checked 1 source file)

• 如何在 mypy 中输入提示ham而不出现错误？或者
• 我应该使用什么策略来代替DEFAULT = object() …