How To Check Whether A Variable Is An Instance Of A Subscripted Generics Defined In Typing?

i.e. How to make this work? python doesn't allow this: from typing import List isinstance(['a', 'b'], List[str]) # TypeError: Subscripted generics cannot be used with class and ins

Solution 1:

Thanks to @user8408080, I find typeguard, but that is not exactly what I want. then I use typeguard to search through stack overflow, and find two more similar library from here:

• typesentry
• enforce

Finally, I got what I want as follows

import typesentry
from typing importList

string_list = ['nobody', 'expects', 'the', 'spanish', 'inqusition']
string_list_class = List[str]

tc1 = typesentry.Config()
is_typed = tc1.is_type  # equivalent of isinstance()

is_typed(string_list,string_list_class)