Python：列表变量作为无类型传递[关闭]

Question

在这里学习 Python，对于任何无知深表歉意。背景 - 制作井字游戏的作业。完成了目标，但现在正在尝试处理异常。在某一时刻，由于某种原因，我的一个变量被无类型传递。下面列出了有问题的代码choice 是有问题的变量，应该是一个列表。奇怪的是它可以正常工作，除非用户首先在板上选择一个已经选择的位置，然后在函数的下一次迭代中发生故障。

def user_choice():
    global board
    row_choice = 0
    column_choice = 0
    if player_1 == True:  # check whose turn
        print("Player 1, ")
    else:
        print("Player 2, ")
    while row_choice not in [1, 2, 3]:  # loop until input is correct
        row_choice = int(input("\tPlease select the row in which you would like to place your mark" +
                               " (1, 2, or 3 from top to bottom): "))
        if row_choice not in [1, 2, 3]:
            print("Sorry, you did not pick a valid number")
    while column_choice not in [1, 2, 3]:  # loop until input is correct
        column_choice = int(input("\tPlease select the column in which you would like to place your mark" +
                                  " (1, 2, or 3 from left to right): "))
        if column_choice not in [1, 2, 3]:
            print("Sorry you did not pick a valid number")
    choice = [(row_choice - 1), (column_choice - 1)]  # assign user input to list
    if board[choice[0]][choice[1]] != " ":  # checks to see if spot already has a mark in it
        print("Sorry, the other player has already picked that spot. Please pick another spot.")
        user_choice()
    else:
        # print(choice)
        # print(type(choice))
        return choice

我很想听听其他方法，但我想知道这里发生了什么（请用初学者的话！）

如果需要，我的代码中引发错误的实际部分是

def update_board(choice):
    global board
    if player_1 == True:
        board[choice[0]][choice[1]] = 'X'  # replace nested list index with user input according to list passed
    else:
        board[choice[0]][choice[1]] = 'O'

board = [[' ', ' ', ' '], [' ', ' ', ' '], [' ', ' ', ' ']]



def game_on():
    answer = input("Ready to play (Y/N)? ").upper()
    if answer == "Y":
        while winner == " ":
            print_board()
            update_board(user_choice())
            test_win()
            change_player()
        game_over()
    elif answer == "N":
        print("No problem, run program again when you are ready.")
    else:
        print('Not a valid input. Please restart the program.')

编辑：固定缩进/添加了board 变量/添加了驱动游戏的主函数game_on。抱歉，3 天来一直在努力学习糟糕的术语。

Answer 1

我认为这是因为您在检查该位置是否可用后没有在第 22 行返回user_choice()。现在您只需再次运行该函数，但您仍然返回choice 变量，用户已在其中选择了一个拍摄点。

所以要解决这个问题，您应该在user_choice 函数中将user_choice() 替换为return user_choice()。

希望它有效:)