python - 在不使用 break 的情况下跳出 python 循环

Question

while answer  == 'Y':
    roll = get_a_roll()
    display_die(roll)
    if roll == first_roll:
        print("You lost!")
    amount_won = roll
    current_amount = amount_earned_this_roll + amount_won
    amount_earned_this_rol = current_amoun
    print("You won $",amount_won)
    print(  "You have $",current_amount)
    print("")
    answer = input("Do you want to go again? (y/n) ").upper()


if answer == 'N':
    print("You left with $",current_amount)
else:
    print("You left with $",current_amount)

这里使用此循环的目的是在游戏中掷骰子，并且根据掷骰的次数获得奖励，除非您掷的骰子与第一次掷骰相匹配。现在，如果发生这种情况，我需要循环停止，而且我知道这很容易使用 break 语句实现，但是，我被告知不允许使用 break 语句。如果 roll == first_roll，我还能如何让循环终止？

Answer 1

您可以:

• 使用标志变量；您已经在使用一个，只需在此处重复使用即可:

  running = True
  while running:
      # ...
      if roll == first_roll:
          running = False
      else:
          # ...
          if answer.lower() in ('n', 'no'):
              running = False
          # ...
  

• 从函数返回:

  def game():
      while True:
          # ...
          if roll == first_roll:
              return
          # ...
          if answer.lower() in ('n', 'no'):
              return
          # ...
  

• 引发异常:

  class GameExit(Exception):
      pass
  
  try:
      while True:
          # ...
          if roll == first_roll:
              raise GameExit()
          # ...
          if answer.lower() in ('n', 'no'):
              raise GameExit()
          # ...
  except GameExit:
      # exited the loop
      pass