Confusing error message for Tuple in runtime context.

[ilevkivskyi]

This code:

from typing import Tuple

Tuple[int]

fails with a strange message.

Value of type "object" is not indexable

I believe this should not be an error at all.

[vilmibm]

I'm not able to reproduce this as of 38453c0 in python 3.5.

[ilevkivskyi]

I still see the same error on the current master.

[vilmibm]

hm, here's what I'm doing:

(mypy) ➜  mypy git:(master) ✗ python
Python 3.5.2 (default, Nov 17 2016, 17:05:23) 
[GCC 5.4.0 20160609] on linux
>>> from typing import Tuple
>>> Tuple[int]
typing.Tuple[int]

I'm happy to investigate more if you have suggestions on other ways to reproduce.

[ilevkivskyi]

You should save the above code in a file and check the file with mypy (runtime context here means that Tuple[int] is not an annotation here).

I can even say why this happens: Tuple is defined just as object() in typing.pyi (to prevent many possible illegal uses of Tuple). I am not sure however what is the right way to fix this.

[vilmibm]

shit sorry, i misunderstood the original issue - i thought runtime context meant "when running the code." apologies!

[mistermocha]

Implementing a common base class with a __getitem__ across Tuple and others in typeshed appears to correct this issue. Suggesting changes in python/typeshed#1340 to address.

[ilevkivskyi]

This is now fixed by python/typeshed#1340

[gvanrossum]

But it won't be effective in mypy master until the next typeshed sync right?