Post on type hints

[TomAugspurger]

Would anyone (possibly @simonjayhawkins, @WillAyd) be interested in writing a post on adding type hints to pandas?

These posts seem to be pretty popular (https://dropbox.tech/application/our-journey-to-type-checking-4-million-lines-of-python and https://blog.zulip.org/2016/10/13/static-types-in-python-oh-mypy/ made the rounds when they were released). And I think pandas is somewhat uniquely positioned given that we have a huge codebase, we're one of the first projects in the numeric python ecosystem to add type hints, and we have a ton of first time contributors.

I think the post could outline

1. Motivations for adopting types in the first place
2. Getting started with typing on a large code base
3. Helping contributors with typing
4. Pain points

I'm happy to assist with writing on this, but hopefully someone more familiar with typing can take the lead.

[WillAyd]

@simonjayhawkins are you already working on this? Tom mentioned on the call today that you were interested, so curious if you've already started. If not happy to partner up