Attempt to improve function under-application and over-application errors

[ChrisPenner]

Overview

WIP; don't review the code yet, still in experimental stages 🧑‍🔬

tester = do
  (each [1] +1 99 (288 + 99))

Before:

After:

Function under-application detection:

threeArgs :  Nat -> Int -> Text -> ()
threeArgs a b c = ()

tester : ()
tester =
  threeArgs 1

Before

After

Implementation notes

How does it accomplish it, in broad strokes? i.e. How does it change the Haskell codebase?

Interesting/controversial decisions

Include anything that you thought twice about, debated, chose arbitrarily, etc.
What could have been done differently, but wasn't? And why?

Test coverage

Have you included tests (which could be a transcript) for this change, or is it somehow covered by existing tests?

Would you recommend improving the test coverage (either as part of this PR or as a separate issue) or do you think it’s adequate?

If you only tested by hand, because that's all that's practical to do for this change, mention that.

Loose ends

Link to related issues that address things you didn't get to. Stuff you encountered on the way and decided not to include in this PR.

[pchiusano]

Wow, awesome!!!