子程序的值未返回/刷新python

Question

I have created a program that asks for the player's movement, and then the player moves within the grid. I have also attempted to validate the input so that the player does not move beyond the limits of the grid, and to do so it calls the function that asks for the player's move, so that they can continue entering their move until it is a valid move. However, the x_move and y_move are not being updated when the function is called again, meaning the user is continuously asked to re-enter their input even when it is now valid. I think it's to do with the return of the values x_move and y_move as when I printed them after taking the user's new input, they stayed the same? My code is below:

def get_move():
    advice  = 'Please enter your move in two integers, vertical, then horizontal, separated by a space.  Use positive numbers for up and right, negative for down and left.'
    example = 'For example, an input of \'2 2\' would be 2 moves vertically, and 2 moves horizontally.'
    #Here I am joining the two inputs for ease of input for the user and so that the input is easier to work with than two serparate ones. Not sure how this will work yet with validation...
    move = input(advice + example)
    coor=move.split()
    while len(coor)!=2:
        print('Invalid input- too many or too few co-ordinates')
        print('')
        advice  = 'Please enter your move in two integers, vertical, then horizontal, separated by a space.  Use positive numbers for up and right, negative for down and left.'
        example = 'For example, an input of \'2 2\' would be 2 moves vertically, and 2 moves horizontally.'
        #Here I am joining the two inputs for ease of input for the user and so that the input is easier to work with than two serparate ones. Not sure how this will work yet with validation...
        move = input(advice + example)
        coor=move.split()
    #Here I am splitting the input using whitespace, hence why nothing is in the bracket
    move = move.split()
    #Now I am declaring the variables that are assigned to the split move input
    y_move,x_move=move
    #And now assigning them as integers
    x_move = int(x_move)
    y_move = int(y_move)
    return x_move, y_move








def update_board(b, current_y_loc, current_x_loc):
    while (-1>= current_y_loc-y_move) or (current_y_loc-y_move>size_of_grid):
        print('INVALID INPUT')
        get_move()
    while (-1>= current_x_loc+x_move) or (current_x_loc+x_move>size_of_grid):
        print('INVALID INPUT')
        get_move()
    b[current_y_loc-y_move][current_x_loc+x_move] = player_location
    current_y_loc -= y_move
    current_x_loc += x_move
    print("current location = ", current_x_loc, current_y_loc)
    return current_y_loc, current_x_loc

Answer 1

您实际上需要将输出从get_move()传递到x_move和y_move即x_move, y_move = get_move()

Answer 2

I think it's to do with the scope of the x_move and y_move variables. They're declared and assigned values in get_move() , but then referenced in update_board() before that.

I'd try adding x_move,y_move=get_move() to update_board() , before the while statements, and changing the call to get_move() inside the while statements to match.

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Additionally, this is slightly outside the scope of the question, but I'd try to rewrite the while loops so that you instead have one loop that checks all four conditions at the same time, or else you could end up with the following outcome:

1. User enters values out of bounds for y
2. first while loop triggered, code asks for new values
3. user enters acceptable y value but out of bounds value for x
4. first while loop exited, second loop triggered by unacceptable x value, asks for new values
5. user enters acceptable x value, but unacceptable y value
6. second while loop exited, code proceeds with out of bounds y value