brittany 0.12 doesn't recognised strictness annotations in GADTs

lspitzner / brittany

haskell source code formatter

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brittany 0.12 doesn't recognised strictness annotations in GADTs #261

Open infinity0 opened 5 years ago

infinity0 commented 5 years ago

$ cat Test.hs

{-# LANGUAGE GADTs #-}
data X where
  X :: !Int -> X

main :: IO ()
main = pure ()

$ brittany Test.hs
ERROR: brittany pretty printer returned syntactically invalid result.
70
$ brittany --version
brittany version 0.12.0.0
Copyright (C) 2016-2018 Lennart Spitzner
There is NO WARRANTY, to the extent permitted by law.

lspitzner commented 5 years ago

This very likely is the same underlying issue as #242, so

this comes down to a bug in ghc-exactprint (https://github.com/alanz/ghc-exactprint/issues/79).
Does not appear wtih ghc<8.6.

(We really want our own GADT layouting to avoid this ..)