为什么我会得到这个索引错误？

Question

我正在尝试为LPTHW做一个额外的学分分配，我想我可能在尝试一些我不知道函数真正用途的东西。我试图测试购买东西，特别是在我的代码中，如果用户购买了一个项目，它会从当前项目列表中弹出该项目，并用新的项目替换它。当我测试购买函数时，我得到了一个索引错误。你有什么办法让它正常工作吗？你知道吗

def buy_weapon(weapons):
    """big bit of code that allows you to buy a weapons from a weapon list.
The function acts a little differently after level zero weapons"""
    global current_weapon
    if weapons == level_zero_weapons:
        sword_price = level_zero_price()
        blunt_price = level_zero_price()
        agile_price = level_zero_price()
        print t.bright_yellow_on_magenta + """
Please type in the weapon you want to buy.

%s, price: %d gold pieces

%s, price: %d gold pieces

%s, price: %d gold pieces.
""" % (weapons[0], sword_price, weapons[1], blunt_price,weapons[2], 
       agile_price)

        weapon_choice = raw_input(":> ")
        if "sword" in weapon_choice:
            current_weapon = weapons[0]
            inventory(weapons[0])
            character_sheet.append(current_weapon)
        elif weapons[1] in weapon_choice:
            current_weapon = weapons[1]
            inventory(weapons[1])
            character_sheet.append(current_weapon)
        elif weapons[2] in weapon_choice:
            current_weapon = weapons[2]
            inventory(weapons[2])
            character_sheet.append(current_weapon)
        else: 
            print "I dont know what %s means" % weapon_choice
            buy_weapon(level_zero_weapons)

    elif weapons == level_one_weapons:
        sword_price = level_one_price()
        blunt_price = level_one_price()
        agile_price = level_one_price()
        print"""
Type in the weapon you want to buy, type quit to return to the barracks.

%s, price: %d gold pieces

%s, price: %d gold pieces

%s, price: %d gold pieces.
""" % (weapons[0], sword_price, weapons[1], blunt_price, weapons[2],
       agile_price)

        weapon_choice = raw_input(":> ")
        if weapons[0] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[0]
            inventory(weapons[0])
            character_sheet.append(current_weapon)
        elif weapons[1] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[1]
            inventory(weapons[1])
            character_sheet.append(current_weapon)
        elif weapons[2] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[2]
            inventory(weapons[2])
            character_sheet.append(current_weapon)
        else: 
            print "I dont know what %s means" % weapon_choice
            buy_weapon(level_one_weapons)

    elif weapons == level_two_weapons:
        sword_price = level_two_price()
        blunt_price = level_two_price()
        agile_price = level_two_price()
        print"""
Type in the weapon you want to buy, type quit to return to the barracks.

%s, price: %d gold pieces

%s, price: %d gold pieces

%s, price: %d gold pieces.
""" % (weapons[0], sword_price, weapons[1], blunt_price,weapons[2], 
       agile_price)

        weapon_choice = raw_input(":> ")
        if weapons[0] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[0]
            inventory(weapons[0])
            character_sheet.append(current_weapon)
        elif weapons[1] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[1]
            inventory(weapons[1])
            character_sheet.append(current_weapon)
        elif weapons[2] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[2]
            inventory(weapons[2])
            character_sheet.append(current_weapon)
        else: 
            print "I dont know what %s means" % weapon_choice
            buy_weapon(level_two_weapons)

    elif weapons == level_three_weapons:
        sword_price = level_three_price()
        blunt_price = level_three_price()
        agile_price = level_three_price()
        print"""
Type in the weapon you want to buy, type quit to return to the barracks.

%s, price: %d gold pieces

%s, price: %d gold pieces

%s, price: %d gold pieces.
""" % (weapons[0], sword_price, weapons[1], blunt_price,weapons[2], 
       agile_price)

        weapon_choice = raw_input(":> ")
        if weapons[0] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[0]
            inventory(weapons[0])
            character_sheet.append(current_weapon)
        elif weapons[1] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[1]
            inventory(weapons[1])
            character_sheet.append(current_weapon)
        elif weapons[2] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[2]
            inventory(weapons[2])
            character_sheet.append(current_weapon)
        else: 
            print "I dont know what %s means" % weapon_choice
            buy_weapon(level_three_weapons)

    elif weapons == level_four_weapons:
        sword_price = level_four_price()
        blunt_price = level_four_price()
        agile_price = level_four_price()
        print"""
Type in the weapon you want to buy, type quit to return to the barracks.

%s, price: %d gold pieces

%s, price: %d gold pieces

%s, price: %d gold pieces.
""" % (weapons[0], sword_price, weapons[1], blunt_price,weapons[2], 
       agile_price)

        weapon_choice = raw_input(":> ")
        if weapons[0] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[0]
            inventory(weapons[0])
            character_sheet.append(current_weapon)
        elif weapons[1] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[1]
            inventory(weapons[1])
            character_sheet.append(current_weapon)
        elif weapons[2] in weapon_choice:
            character_sheet.pop(current_weapon)
            current_weapon = weapons[2]
            inventory(weapons[2])
            character_sheet.append(current_weapon)
        else: 
            print "I dont know what %s means" % weapon_choice
            buy_weapon(level_four_weapons)      
    else:
        print"~~~There is a bug somwhere, forgot to assign (weapons)\n\n\n"
    raw_input(t.white_on_red("""
Your current weapon is now a %s. Press Enter To Continue
""" % current_weapon))

# Weapon lists 
level_zero_weapons = ['short sword', 'club', 'dagger']
level_one_weapons = ['sword' 'mace', 'rapier']
level_two_weapons = ['long sword', 'morningstar', 'trident']
level_three_weapons = ['claymore', 'flail', 'sycthe']
level_four_weapons = ['bastard sword, dragon bone, crystal halbred']

这里是我尝试运行文件的地方。你知道吗

pp.pprint(character_sheet)
raw_input(t.white_on_red("Please Press Enter To Buy A Weapon"))
buy_weapon(level_zero_weapons)
buy_weapon(level_one_weapons)
pp = pprint.PrettyPrinter(indent=30)
pp.pprint(character_sheet)

最后是我的输出。你知道吗

Your current weapon is now a dagger. Press Enter To Continue

Traceback (most recent call last):
  File "lodarena.py", line 398, in <module>
    character_gen()
  File "lodarena.py", line 393, in character_gen
    buy_weapon(level_one_weapons)
  File "lodarena.py", line 139, in buy_weapon
    """ % (weapons[0], sword_price, weapons[1], blunt_price, weapons[2], agile_price)
IndexError: list index out of range
Raymond-Weisss-MacBook-Pro:lodarena Raylug$ 

我正在使用Python2.7

Answer 1

在buy_weapons函数中，将第一行设为“打印武器”以调试代码。你可能没有传递你认为传递的东西

当您学习python时，您正在做我们大多数人在第一次学习一种语言时所做的相同的事情，您可能需要研究一些数据结构。我猜您还没有为对象做好准备，但是使用嵌套字典可能是值得的，例如：

weapons = {1 : {'sword': {'name':'name here',
                            'price': 123},
                  'blunt': {'name':'name here',
                            'price': 123},
                  'agile': {'name':'name here',
                            'price': 123},
                  },
           2 : {'sword': {'name':'name here',
                            'price': 123},
                  'blunt': {'name':'name here',
                            'price': 123},
                  'agile': {'name':'name here',
                            'price': 123},
                  },
          #add levels as you need
          }

基本上，你正在创建一个奇特的查找类型的东西，它跟踪，等级，然后武器类型，名称和价格，你可以像这样访问它们：

level = 1
type = 'sword'
weaponname = weapons[level][type]['name']
weaponprice = weapons[level][type]['price']