diff options
Diffstat (limited to 'src/Xanthous/Data.hs')
-rw-r--r-- | src/Xanthous/Data.hs | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/src/Xanthous/Data.hs b/src/Xanthous/Data.hs index afba273005f8..ff9da6280bfb 100644 --- a/src/Xanthous/Data.hs +++ b/src/Xanthous/Data.hs @@ -1,3 +1,4 @@ +{-# LANGUAGE RoleAnnotations #-} {-# LANGUAGE RecordWildCards #-} {-# LANGUAGE DeriveTraversable #-} {-# LANGUAGE DeriveFoldable #-} @@ -74,6 +75,7 @@ data Positioned a where Positioned :: Position -> a -> Positioned a deriving stock (Show, Eq, Ord, Functor, Foldable, Traversable, Generic) deriving anyclass (CoArbitrary, Function) +type role Positioned representational _Positioned :: Iso (Position, a) (Position, b) (Positioned a) (Positioned b) _Positioned = iso hither yon |