在赋值之前引用的封闭行中分配的局部变量

Question

我有这段代码

health = 12

manager_health = 10 

def manager_boss_fight_used_for_backup():

    sleep(1)
    print("manager health is ",manager_health)
    print("your health is ",health)
    
    sleep(1)

    print("the boss gets first attack")
    manager_boss_damage = random.randint(1,8)
    print(manager_boss_damage)
    print(health)
    health = health - manager_boss_damage
    sleep(1)
    print("the boss did",manager_boss_damage,"damage")
    sleep(1)
    print("your health is now",health)

    if health <= 0:
        sleep(1)
        print("you have died")
        sleep(1)
        print("better luck next time")
        exit()
    sleep(1)
    print("your turn to attack")
    sleep(1)
    heal_or_attack = input("Do you wish to heal or attack?(1/2)")
    if heal_or_attack == "1":
        healing = random.randint(1,7)
        print("you have healed by",healing)
        health = health + healing
        manager_boss_fight_used_for_backup()
    if heal_or_attack == "2":
        print("you attack the boss")
        sleep(1)
        attack_damage = random.randint(1,6)
        print("You did",attack_damage,"damage")
        manager_health = manager_health - attack_damage
        if manager_health <= 0:
            sleep(1)
            print("You have killed the boss")
            sleep(1)

        if manager_health > 0:
            manager_boss_fight_used_for_backup()

，在代码部分中，例如 health = health - manager_boss_damage 它将出错。我摆弄了全局变量和所有这些，但我无法让它工作，所以我来到这里。任何答案表示赞赏！

Answer 1

也许每个人都会告诉你，使用全局变量是非常糟糕的。为什么不使用 OOP 来代替呢？您可以创建一个 class Manager: 和一个 class Player:，其中 health 作为属性，damage 和 take_damage 作为该类的方法，例如：

class Manager:
def __init__(self):
    self.health = 10
    
def attack(self):
    damage = ramdom.randint(1,8)
    return damage
def take_damage(self, damage):
    self.health -= damage
    if (self.health <= 0):
        self.health = 0
    return self.health

那么 Player 类将是或多或少相同：

class Player:
def __init__(self):
    self.health = 12
    
def attack(self):
    damage = ramdom.randint(1,8)
    return damage
def take_damage(self, damage):
    self.health -= damage
    if (self.health <= 0):
        self.health = 0
    return self.health
def heal(self, amount):
    self.health += amount
    return self.health

当然，理想情况下，您可以创建一个名为“Actor”或“Enemy”的类并从那里派生它们，但现在让我们坚持这一点：

# Instantiate the classes like this:
manager = Manager()
player = Player()
# and then just invoke the methods from the classes:
sleep(1)
print("manager health is ",manager.health)
print("your health is ",player.health)

sleep(1)

print("the boss gets first attack")
damage = manager.Attack()
print("You were hit by {} points".format(damage))
player.take_damage(damage)
print("Your Health is {}".format(player.health))

等等。

Answer 2

每当您在 manager_fight_used_for_backup() 函数内对 health 进行赋值时，Python 都会默认尝试分配一个名为 health 的新变量。

最快的修复方法是在函数体的开头使用 global 关键字，以明确您引用的是函数外部的 health 变量

global health

：会告诉 Python 您正在引用函数外部的 health 变量。 但是，最好的解决方案是重构此代码，以便函数不会修改共享的全局状态。