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Python: 打字: 功能上不起作用的 Typhints
原标题:Python: typing: Typehints on function not working
I m having trouble getting type hints to work in the following example. Can anyone see what is wrong. The 2nd and 3rd example works fine. The first one fails when i run it #python 3.6 from typing import List, Tuple # line 5 below where error occurs def func(x: List[int, str]) -> int: return 1 a = func([1, "a"]) # OK def func2(x: Tuple[int, str]) -> int: return 1 b = func2((1, "a")) # OK def func3(x: List[Union[str, int]]) -> int: return 1 c = func3((1, "a")) Here is the stack trace. I can t work out what is wrong. Traceback (most recent call last): File "C:scratch/scratch2.py", line 5, in def func(x: List[int, str]) -> int: File "C:Miniconda3lib yping.py", line 682, in inner return func(*args, **kwds) File "C:Miniconda3lib yping.py", line 1152, in __getitem__ _check_generic(self, params) File "C:Miniconda3 yping.py", line 662, in _check_generic ("many" if alen > elen else "few", repr(cls), alen, elen)) TypeError: Too many parameters for typing.List; actual 2, expected 1
最佳回答
The typing library will only accept one argument to the List type
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