anchor.diff:                                      TyreKind = parseTyreKind s.Tires
                                       Economy = parseEconomy s.Driving_style
                                       AirCon = parseAirCon s.Ac
  -                                    BcConsumption = Option.someIf (fun x -> x <> 0.) (float s.Bc_consumption)
  -                                    BcAvgSpeed = Option.someIf (fun x -> x <> 0.) (float s.Bc_avg_speed)
  +                                    BcConsumption = Option.filter (fun x -> x <> 0.) (Some (float s.Bc_consumption))
  +                                    BcAvgSpeed = Option.filter (fun x -> x <> 0.) (Some (float s.Bc_avg_speed))
  +                                    RouteSplit = routeSplit s.Route_city s.Route_country s.Route_motorway
  +                                    Notes = s.Notes
                                   })
               |> Seq.sortBy (fun f -> f.Date)
               |> JsonConvert.SerializeObject
   
  +let setJson = Suave.Writers.setHeader "Content-Type" "application/json"
  +
   let webPart =
       choose [
  -        path "/" >=> OK data
  +        path "/" >=> OK data >=> setJson
       ]
   
   startWebServer defaultConfig webPart
  
positive.code:     AirCon : AirCon
      BcConsumption : float option
      BcAvgSpeed : float option
  }
  
  let parseFuelingKind = function
  
negative.code: open FSharp.Data
  open Newtonsoft.Json
  
  type Percentage = byte
  
  type FuelingKind = Full | Half
  type AirCon = AcOff | AcOn of Percentage
  type TyreKind = Summer | Winter | Universal
  type Economy = High | Average | Low
  
  type RouteSplit = {
      City : Percentage
      Country : Percentage
      Motorway : Percentage
  }
  
  type Fueling = {
      Date : DateTime
  