Make servant-foreign code nicer

[dredozubov]

I felt like i have to do this before addressing a few other issues with servant-foreign

Basically it's:

• non-messy imports
• got rid of most long lines (>80 chars)
• prisms for sum types and newtypes(we use lens anyway, so why not)
• consistent indentation

Also i made some changes to demonstrate my point from #345 (comment)

[dredozubov]

If you too feel like it looks more readable this way, maybe i'll go through other packages with this PR

[fizruk]

Nice! 👍

Would be even nicer if you add a proper haddock documentation!
Would be magical if you also document design choices and intended usage!

No pressure though :)

[dredozubov]

@fizruk, i plan to do that after i'll properly address #351 ;) After some consideration i feel like there may be some design changes on its way.

[purcell]

This is all great, but it'd be a big job to rebase #351 on top of it. Let me know if you want a hand with anything.

[jkarni]

👍 - @dredozubov can we merge?

[dredozubov]

@jkarni sure, but i also wonder if it's worth doing repo-wise. I'd be more than happy to see it, but it contradicts the

Though we aren't sticklers for style

from https://github.com/haskell-servant/servant/blob/master/CONTRIBUTING.md

[dredozubov]

@purcell i started doing servant-rust to test the design, but my day work consumes the most of my time, so i kinda feel that i don't want to rush #351, it can always land in 0.5.1 or something

[purcell]

Fair enough, and this is a nice tidy-up. Do you think it'd be helpful if I try to rebase #351 on top of this now? Or do you already know my approach there wouldn't be optimal?

[dredozubov]

@purcell i'll be able to tell a bit later, don't hurry with rebasing it. Are you on irc btw?

[purcell]

i'll be able to tell a bit later, don't hurry with rebasing it. Are you on irc btw?

Ah, no, sorry, but I'm on github a lot and happy to discuss. And happy to pop onto IRC at some point if it'd help.