Python：从不同的函数添加到列表中

Question

我已经发布了一个类似的问题，但我没有得到正确的答案，可能是因为我不太清楚我希望我的程序运行的方式。

我正在写一个简单的礼物添加程序，我想给一个在不同功能的字典中的人添加礼物。

def main():

    print("Select: ")

    print("\n\n\t1. Gifts")

    selection_1 = input()

    if selection_1 == "1":
        people_list()
        return selection

    else:
        print("Type a number for selecting.")
        main()

def people_list():

    people = {"Elena":["book","candy","sweater"],
             "Daria":["healthy food"],
             "Petra and Rok":[],
             "Nikola":["cheese"],
             "Matija + Elena":["vacation"],
             "Christian":["chocolate"]}

    print ("""Select a person to show their gifts:

        1. Elena
        2. Daria
        3. Petra and Rok
        4. Nikola
        5. Matija + Elena
        6. Christian

    """)
    gifts(people)


def gifts(people):

    selection_2 = input()

    if selection_2 == "1":
        person = people["Elena"]
        print(people["Elena"])
        manage_gifts(person, people)
        return person
    elif selection_2 == "2":
        person = people["Daria"]
        print(people["Daria"])
        manage_gifts(person, people)
        return person
    elif selection_2 == "3":
        person = people["Petra and Rok"]
        print(people["Petra and Rok"])
        manage_gifts(person, people)
        return person
    elif selection_2 == "4":
        person = people["Nikola"]
        print(people["Nikola"])
        manage_gifts(person, people)
        return person
    elif selection_2 == "5":
        person = people["Matija + Elena"]
        print(people["Matija + Elena"])
        manage_gifts(person, people)
        return person
    elif selection_2 == "6":
        person = people["Christian"]
        print(people["Christian"])
        manage_gifts(person, people)
        return person
    else:
        print("Choose a person from the list!")
        people_list()
    return person

def manage_gifts(person, people):


    print("""
        1. Add gift""")

    gift_option = input()

    if gift_option == "1":
        print("\nType the gift you would like to add?\n")
        new_gift = input()
        people[person].append(str(new_gift))
        print("Gift added: ", people[person])

main()

我希望将新礼物添加到我从列表中选择的“人物”中。我得到的错误是：

Traceback (most recent call last):
  File "E:/Python/Vaje_Book/Gifts.py", line 92, in <module>
    main()
  File "E:/Python/Vaje_Book/Gifts.py", line 10, in main
    people_list()
  File "E:/Python/Vaje_Book/Gifts.py", line 36, in people_list
    gifts(people)
  File "E:/Python/Vaje_Book/Gifts.py", line 46, in gifts
    manage_gifts(person, people)
  File "E:/Python/Vaje_Book/Gifts.py", line 89, in manage_gifts
    people[person].append(str(new_gift))
TypeError: unhashable type: 'list'

非常感谢您的帮助。

Answer 1

在gifts(people)： 当你做person = people["Elena"]时，person是列表类型。

然后在manage_gifts(person, people)： 当你做people[person].append(str(new_gift))，然后错误TypeError: unhashable type: 'list'逻辑上提出因为人是一个列表。它应该是一个字符串。

我认为在gifts(people)，人们应该用person = people["Elena"]取代person = "Elena"。等等person变量的其他任务。

但是，在此代码中还有其他错误需要修复： - 不要在main()里面打电话给main() - 不要在main()返回任何东西

Answer 2

我没有足够的代表评论，但你应该知道在主函数末尾调用main()并不是一个好的形式。 Python不进行尾调用优化，所以最终你会耗尽堆栈并以这种方式崩溃。把整个东西放在while循环中。例如。

def main（）：

while True:
    print("Select: ")

    print("\n\n\t1. Gifts")

    selection_1 = input()

    if selection_1 == "1":
        people_list()
        return selection

    else:
        print("Type a number for selecting.")