On 2015-10-22 at 08:04:10 +0200, Taru Karttunen wrote: [...]
B) There is an automated tool that can be used to fix most code to compile with new versions of GHC without warnings or CPP.
Fyi, Alan is currently working on levaraging HaRe[1] in https://github.com/alanz/Hs2010To201x (the `parsing-only` branch) and it's already showing great promise. However, tools like this will only be able to handle the no-brainer cases, as in general it's a NP hard problem. But luckily, those boring mechanical refactorings usually represent the vast majority, and that's the tedious work we want tooling to assist us most with.
C) Hackage displays vocally what works with which versions of GHC (Status reports do help somewhat)
I.e. something like http://matrix.hackage.haskell.org/package/text ? :-) [1]: Btw, here's a recent talk which also mentions the use-case of using HaRe to update between Haskell Report revisions or `base` versions: https://skillsmatter.com/skillscasts/6539-a-new-foundation-for-refactoring-g...