在学习跨类调用时遇到问题

Question

跨类调用问题

class Player:
    def __init__(self,game_player):
        self.game_player = game_player
    def atk(self,game_enemy):
        self.game_enemy = game_enemy
        print(f"{self.game_player}使用{self.Enemy.game_skill}攻击了敌人")
        self.game_enemy.suffer_beating()
class Enemy:
    def __init__(self,game_skill):
        self.game_skill = game_skill
    # def __str__(self):
    #     return f"{self.}"
    def suffer_beating(self):
        print(f"{self.Play.game_enemy}受伤了,头顶爆字")
CJ = Player("321")
power = Enemy("123")
CJ.atk("xz")

跨类没有办法使用变量

报错：

Traceback (most recent call last):
  File "/home/tarena/month01/day11/homeworlk.py", line 26, in <module>
    CJ.atk("xz")
  File "/home/tarena/month01/day11/homeworlk.py", line 15, in atk
    print(f"{self.game_player}使用{self.Enemy.game_skill}攻击了敌人")
AttributeError: 'Player' object has no attribute 'Enemy'

我希望能正确输出我代码中两个print的内容

Answer 1

你这样是循环引用的，不建议用A引用B,B在引用A。想想在构造A对象的时候，B对象还没有建立，就初始化A对象这是不好的做法，尽管也有办法塞入进去，但Python采用的是引用计数法对内存进行回收的，这样的内存会导致内存泄漏的产生。如下代码改成:

class Enemy:
    def __init__(self, game_skill):
        self.game_skill = game_skill

    def suffer_beating(self):
        print(f"{self.game_skill}受伤了,头顶爆字")


class Player:
    def __init__(self, game_player, enemy: Enemy):
        self.game_player = game_player
        self.Enemy = enemy

    def atk(self):
        print(f"{self.game_player}使用{self.Enemy.game_skill}攻击了敌人")
        self.Enemy.suffer_beating()


power = Enemy("123")
CJ = Player("321", power)
CJ.atk()