position method

ChessFen position()

创建当前局面下的子力位置

Implementation

ChessFen position() {
  int chr = 65;
  String fenStr = fen;
  String positionStr = fenStr.replaceAllMapped(
    RegExp(r'[^0-9\\/]'),
    (match) => String.fromCharCode(chr++),
  );
  // print(positionStr);
  return ChessFen(positionStr);
}