purescript-0.12.0: tests/purs/docs/src/Desugar.purs
module Desugar where data X a b = X a b test :: forall a b. X (a -> b) a -> b test x = let X a b = x in a b
module Desugar where data X a b = X a b test :: forall a b. X (a -> b) a -> b test x = let X a b = x in a b