How are array typehints declared in Python? [duplicate]

Question

Given this function:

def array_returner():
    return ["hello", "there"]

How would I typehint that this function returns an array of strings, without importing List (and using the List[str] syntax)?

Duplicate: How to properly function annotate / type hint a list of strings — Georgy
– Georgy, Commented Dec 8, 2019 at 20:03
@Georgy These questions address Lists, not arrays. I don't want to import List. (and list[str] evidently does not work) — Newbyte
– Newbyte, Commented Dec 8, 2019 at 20:25
I think you need exactly the list, as your example function returns a list, not an "array". Even if it's not the case, I don't get why you want to avoid using List[str], and at the same time you accepted an answer that proposed it. Could you clarify, please? — Georgy
– Georgy, Commented Dec 8, 2019 at 20:35
Another duplicate: How can I create a type hint that my returned list contains strings? — Georgy
– Georgy, Commented Dec 8, 2019 at 20:43

azro · Accepted Answer · 2024-03-06 17:50:42Z

14

Like this

from typing import List
def array_returner() -> List[str]:
    pass

Since python3.9

def array_returner() -> list[str]:
    pass

answered Dec 8, 2019 at 18:59

azro

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Comments

Ian · Accepted Answer · 2019-12-08 18:59:21Z

12

This is what you're looking for:

from typing import List

def array_returner() -> List[str]:
    return ["hello", "there"]

answered Dec 8, 2019 at 18:59

Ian

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