python - Python中的泛型函数类型

Question

我在 Eclipse 4.8 和 Pydev 下的 Linux Ubuntu 18.04 上的 Python 3.7 下运行。

声明:

args:Dict[str: Optional[Any]] = {}

位于从我的测试代码导入的模块中。并且它被标记为来自 typing.py 的以下错误消息:

TypeError: Parameters to generic types must be types. Got slice(<class 'str'>, typing.Union[typing.Any, NoneType], None). The stack trace follows: Finding files... done. Importing test modules ... Traceback (most recent call last):   File "/Data/WiseOldBird/Eclipse/pool/plugins/org.python.pydev.core_7.0.3.201811082356/pysrc/_pydev_runfiles/pydev_runfiles.py", line 468, in __get_module_from_str
    mod = __import__(modname)   File "/Data/WiseOldBird/Workspaces/WikimediaAccess/WikimediaLoader/Tests/wiseoldbird/loaders/TestWikimediaLoader.py", line 10, in <module>
    from wiseoldbird.application_controller import main   File "/Data/WiseOldBird/Workspaces/WikimediaAccess/WikimediaLoader/src/wiseoldbird/application_controller.py", line 36, in <module>
    args:Dict[str: Optional[Any]] = {}   File "/usr/local/lib/python3.7/typing.py", line 251, in inner
    return func(*args, **kwds)   File "/usr/local/lib/python3.7/typing.py", line 626, in __getitem__
    params = tuple(_type_check(p, msg) for p in params)   File "/usr/local/lib/python3.7/typing.py", line 626, in <genexpr>
    params = tuple(_type_check(p, msg) for p in params)   File "/usr/local/lib/python3.7/typing.py", line 139, in _type_check
    raise TypeError(f"{msg} Got {arg!r:.100}.") TypeError: Parameters 

这可以防止我的测试模块被导入。
我究竟做错了什么？

Answer 1

dict 类型的正确语法是

Dict[str, Optional[Any]]

当你写 [a: b] , Python 将其解释为一个切片，即使部分数组起作用的东西，如 a[1:10] .您可以在错误消息中看到这一点: Got slice(<class 'str'>, typing.Union[typing.Any, NoneType], None) .