I agree that `from typing import TYPE_CHECKING` is not desirable from
the import time reduction perspective.
>From my understanding code completion *can* be based on type hinting
to avoid actual code execution.
That's why I've mentioned that typeshed already has the correct type
information.
if TYPE_CHECKING:
import ...
requires mypy modification.
if False:
import ...
Works right now for stdlib (mypy ignores stdlib code but uses typeshed
anyway) but looks a little cryptic.
Requires a comprehensive comment at least.
Last time I looked at this, I'm pretty sure `if False` broke at least one popular static analysis tool (ie it was clever enough to ignore everything inside `if False`) – I think either pylint or jedi?
I'd suggest checking any clever hacks against at least: mypy, pylint/astroid, jedi, pyflakes, and pycharm. They all have their own static analysis engines, and each one has its own idiosyncratic quirks.
We've struggled with this a *lot* in trio, and eventually ended up giving up on all forms of dynamic export cleverness; we've even banned the use of __all__ entirely. Static analysis has gotten good enough that users won't accept it not working, but it hasn't gotten good enough to handle anything but the simplest static exports in a reliable way:
The stdlib has more leeway because when tools don't work on the stdlib then they tend to eventually add workarounds. I'm just saying, think twice before diving into clever hacks to workaround static analysis limits, and if you're going to do it then be careful to be thorough. You're basically relying on undocumented bugs, and it gets really messy really quickly.
-n