anchor.diff:  
       static member relocateCharacter index coordinates gameplay =
           Gameplay.updateChessboard (Chessboard.relocateCharacter index coordinates) gameplay
  -    
  -    static member clearPickups gameplay =
  -        Gameplay.updateChessboard Chessboard.clearPickups gameplay
       
       static member removeEnemy index gameplay =
           match index with
  
positive.code:       MetaMap : MetaMap
        Field : Field
        Chessboard : Chessboard
        CharacterMoves : Map<CharacterIndex, Move>
        Puppeteer : Puppeteer }
  
      static member initial =
          let field = Field.initial
  
negative.code:     
      static member turnInProgress index gameplay =
          Puppeteer.turnInProgress index gameplay.Puppeteer
      
      static member anyTurnsInProgress gameplay = 
          gameplay.Puppeteer.AnyTurnsInProgress
      
      static member isPlayerAttacking gameplay =
          match Gameplay.tryGetCharacterTurn PlayerIndex gameplay with
  