Copy/pasting code from GitLab
(This isn't specifically a migration issue, but then it's not a GHC issue either: it's about using GitLab.)
If I copy/paste code from GitLab comments, it loses linebreaks/indenting and instead gets invisible extra characters that give GHC severe indigestion. They're presumably some sort of markup.
For example copy from this
class C a where
meth :: a -> Bool
instance C Int where
meth = (>= 0)
pastes as per attachedAnnoyingPaste.hs
(Of course pasting it back here works perfectly.)
Copy/paste from Trac worked fine; copy/paste from StackOverflow works fine.