simple purescript that dont werk

try.purescript

module Parse where

import Prelude
import Data.Traversable (scanr)
import Data.List (List(Cons), (:))

data Loc = Loc { line :: Int }

data LocRange
    = LocRange {
        start :: Loc,
        end :: Loc
    }

data CommentNode
    = CommentBlock {
        value :: String,
        loc :: LocRange
    }
    | CommentLine {
        value :: String,
        loc :: LocRange
    }

groupLineComments :: List CommentNode -> List CommentNode
groupLineComments nodes = scanr appendComment nodes []

appendComment :: CommentNode -> List CommentNode -> List CommentNode
appendComment (CommentBlock node) nodes            = node : nodes
appendComment (CommentLine node) (Cons first nodes) = (mergeComments first node) : nodes

-- TODO: merge loc, too:
mergeComments :: CommentNode -> CommentNode -> CommentNode
-- mergeComments a b = CommentLine { value: a.value <> "\n" <> b.value, loc: a.loc }
-- mergeComments a b = CommentLine (a.value <> "\n" <> b.value) a.loc
-- mergeComments a b = CommentLine { value: a.value, loc: a.loc }
mergeComments a b = a