Having just read the Haddock manual , I am haddocking (may I copyleft that verb?) my code. But half-way through this data type, I discover that haddock rejects my non-haddock comments, although GHC is fine: -- | Non-interactive representation of a Chu Shogi move data Move = Pass Piece Coordinate -- ^ Double move to empty square and back to origin | Igui Piece Coordinate -- ^Capture without moving Piece Coordinate -- Captured piece | Double_move Piece -- ^ Other double moves Coordinate -- Initial location Coordinate -- First destination (Maybe Piece) -- Capture? Coordinate -- Second destination (Maybe Piece) -- Capture? | Capture Piece Coordinate Piece Coordinate Bool -- Promote? Bool -- Declined to promote | Move Piece Coordinate Coordinate Bool Bool How can I document the components of each constructor? -- Colin Adams Preston Lancashire