This is gonna be a fun issue...

So a lot of editors try to do code formatting while you are typing, and to varying degrees they all kinda suck at it.

While it's an okay experience to format on save or after the fact, it would be nice if things were auto-formatting while typing.

There's a couple messages in the language-server-protocol for "formatting requests":

• Document Formatting Request
• Document Range Formatting Request
• Document on Type Formatting Request

Each of this represents a different opportunity for prettier to fix the formatting of code.

One of the important pieces here will be that it will be possible to have an invalid program which Babylon will currently reject because the user hasn't finished making it valid. Will have to talk to Babylon folks about implementing a "loose" parser which can recover from mistakes (cc @hzoo @danez).

While the language-server-protocol doesn't work everywhere. If more tools like prettier embraced it, it would push more editors to formally implement it, which would be a nice effect.