如何制作特定可变对象的深层副本？

问题描述

我正在尝试制作一个国际象棋引擎。

def botmove(board):
  legal=list(board.legal_moves)#needed because --->TypeError: 'LegalMoveGenerator' object is not subscriptable
  boardhalfmove=board.pop()
  choosemove(board,boardhalfmove,legal)
  print("Computer moves:",move)
  movepiece(move,board)

但是，我遇到了一个错误：

Traceback (most recent call last):
  File "main.py",line 32,in <module>
    botmove(board)
  File "/home/runner/chess-engine-goal-3minimax/move.py",line 70,in botmove
    choosemove(board,legal)
  File "/home/runner/chess-engine-goal-3minimax/move.py",line 49,in choosemove
    movepiece(str(i),board)
  File "/home/runner/chess-engine-goal-3minimax/move.py",line 4,in movepiece
    moveinput = str(board.push_san(movestr))
  File "/opt/virtualenvs/python3/lib/python3.8/site-packages/chess/__init__.py",line 3003,in push_san
    move = self.parse_san(san)
  File "/opt/virtualenvs/python3/lib/python3.8/site-packages/chess/__init__.py",line 2970,in parse_san
    move = self.find_move(square(from_file,from_rank),to_square,promotion)
  File "/opt/virtualenvs/python3/lib/python3.8/site-packages/chess/__init__.py",line 2272,in find_move
    raise ValueError(f"no matching legal move for {move.uci()} ({SQUARE_NAMES[from_square]} -> {SQUARE_NAMES[to_square]}) in {self.fen()}")
ValueError: no matching legal move for g8h6 (g8 -> h6) in rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

这不好，尤其是 legal move 部分。我回溯到错误的来源：

boardhalfmove=board.pop()

我知道 Python 古怪的可变性，虽然我知道我可以复制这样的列表：

secondlist=list[:]#makes a copy

type(board) 返回<class 'chess.Board'>。
如何制作board的完整副本？
提前致谢。

解决方法

通常，Python 有一个名为“copy”的库，它实现了基本对象的 deepcopy。尝试使用 from copy import deepcopy 并覆盖 Board 的 __eq__ 功能。

有关详细信息，请查看How can I create a copy of an object in Python?

python python-3.x python-chess