typing

来源： https://stackoverflow.com/questions/39458193/using-list-tuple-etc-from-typing-vs-directly-referring-type-as-list-tuple-etc

来源： https://stackoverflow.com/questions/54891752/is-it-possible-to-guarantee-an-array-to-be-sorted-in-typescript

来源： https://stackoverflow.com/questions/54891752/is-it-possible-to-guarantee-an-array-to-be-sorted-in-typescript

来源： https://stackoverflow.com/questions/54891752/is-it-possible-to-guarantee-an-array-to-be-sorted-in-typescript

来源： https://stackoverflow.com/questions/54891752/is-it-possible-to-guarantee-an-array-to-be-sorted-in-typescript

来源： https://stackoverflow.com/questions/62900750/why-does-mypy-reject-my-mixed-union-type-declaration

问题 How can I annotate the yield type of a contextmanager in PyCharm so that it properly guesses the type of the value used in the with clauses - just as it guesses that the f created in with open(...) as f is a file? For example, I have a context manager like this: @contextlib.contextmanager def temp_borders_file(geometry: GEOSGeometry, name='borders.json'): with TemporaryDirectory() as temp_dir: borders_file = Path(dir) / name with borders_file.open('w+') as f: f.write(geometry.json) yield

问题 Let's say I have a python function whose single argument is a non-trivial type: from typing import List, Dict ArgType = List[Dict[str, int]] # this could be any non-trivial type def myfun(a: ArgType) -> None: ... ... and then I have a data structure that I have unpacked from a JSON source: import json data = json.loads(...) My question is: How can I check at runtime that data has the correct type to be used as an argument to myfun() before using it as an argument for myfun() ? if not

问题 Can you spot the error in the code below? Mypy can't. from typing import Dict, Any def add_items(d: Dict[str, Any]) -> None: d['foo'] = 5 d: Dict[str, str] = {} add_items(d) for key, value in d.items(): print(f"{repr(key)}: {repr(value.lower())}") Python spots the error, of course, helpfully informing us that 'int' object has no attribute 'lower' . Too bad it can't tell us this until run time. As far as I can tell, mypy doesn't catch this error because it allows arguments to the d parameter

问题 Can you spot the error in the code below? Mypy can't. from typing import Dict, Any def add_items(d: Dict[str, Any]) -> None: d['foo'] = 5 d: Dict[str, str] = {} add_items(d) for key, value in d.items(): print(f"{repr(key)}: {repr(value.lower())}") Python spots the error, of course, helpfully informing us that 'int' object has no attribute 'lower' . Too bad it can't tell us this until run time. As far as I can tell, mypy doesn't catch this error because it allows arguments to the d parameter