anchor.diff:              match config.LessonToExport with
               | "" -> None
               | l -> Some(l)
  -        this.RunGameExport(config.GameToExport, lessonParam)
  +        let regexParam = 
  +            match config.LessonRegexToExport with
  +            | "" -> None
  +            | l -> Some(l)
  +
  +        this.RunGameExport(config.GameToExport, lessonParam, regexParam)
           ()
positive.code:             finalPairing |> Array.iter(fun (r, p) -> writeCard(r, p)))
          ()
  
      member private this.RunGameExport(game: string, lesson: string option) = 
          match (LLDatabase.Games |> Array.tryFind(fun t -> t.Name = game)) with
          | Some(g) -> 
              let lessonsToExport = 
                  match lesson with
                  | Some(l) when not(l.Contains("*")) -> 
                      LLDatabase.Lessons |> Array.tryFind(fun t -> (t.GameID = g.ID) && (t.Name = l)) |> Option.toArray
                  | Some(l) when l.Contains("*") ->
                      // wildcard
                      let rootName = l.Substring(0, l.IndexOf('*'))
                      LLDatabase.Lessons |> Array.filter(fun t -> (t.GameID = g.ID) && t.Name.StartsWith(rootName))
                  | _ -> LLDatabase.Lessons |> Array.filter(fun t -> t.GameID = g.ID)
  
              use outStream = new StreamWriter(config.ExportPath)
              lessonsToExport |> Array.iter(this.RunLessonExport(g, outStream))
          | _ -> 
              outputTextWriter.WriteLine("Couldn't find entry for game '" + game + "'")
          ()
  
negative.code: 
  open LLDatabase
  open LudumLinguarumPlugins
  open System
  open System.IO
  open System.Text.RegularExpressions
  
  type AnkiExporterConfiguration() = 
      [<CommandLine.Option("game", Required = true)>]
      member val GameToExport = "" with get, set
  
      [<CommandLine.Option("lesson", Required = false)>]
      member val LessonToExport = "" with get, set
  
      [<CommandLine.Option("lesson-regex", Required = false)>]
      member val LessonRegexToExport = "" with get, set
  
      [<CommandLine.Option("export-path", Required = true)>]
      member val ExportPath = "" with get, set
  