sclass PositionCloseOracle {
  // The currently open position
  settable TradingPosition position;
  
  // our loss tolerance (how much of our investment we are
  // prepared to lose in one trade)
  settable double lossTolerancePercent = 10;
  
  // React to a new ticker value coming in
  void addValue(double price, Timestamp timestamp) {
  }
}