為什么我使用 `exec()` 的代碼會拋出錯誤？

Question

我正在做一些詢問你想做什么然后去做的事情。 但是當我調用另一個文件時，它不會讀取整個文件。

這是調用另一個腳本的代碼

if math == "yes":
    exec(open("calculator.py").read());'''

這是被調用的腳本

'''
     else:
        print('You have not typed a valid 
operator, please run the program again.')
# Add again() function to calculate() function
    again()

def again():
    calc_again = input('''
Do you want to calculate again?
Please type Y for YES or N for NO.
''')

    if calc_again.upper() == 'Y':
        calculate()
    elif calc_again.upper() == 'N':
        print('See you later.')
    else:
        again()

calculate()

這是錯誤

    Traceback (most recent call last):
  File "C:\Users\cahen\Desktop\chat bot.py", line 
17, in <module>
    main()
  File "C:\Users\cahen\Desktop\chat bot.py", line 
14, in main
    exec(open("calculator.py").read());
  File "<string>", line 47, in <module>
  File "<string>", line 32, in calculate
NameError: name 'again' is not defined

如果我自己運行calculator.py，它工作正常。只是當我從另一個混亂的腳本調用它時。

Answer 1

很明顯，您嘗試在定義之前調用again函數：

 '''
     else:
        print('You have not typed a valid 
operator, please run the program again.')
# Add again() function to calculate() function
    again()   # <----------------- CALLED HERE

def again():  # <----------------- DEFINED HERE
    calc_again = input('''
Do you want to calculate again?
Please type Y for YES or N for NO.
''')

    if calc_again.upper() == 'Y':
        calculate()
    elif calc_again.upper() == 'N':
        print('See you later.')
    else:
        again()

calculate()