Python面向对象编程——一些类定义（杂）

一、abstractmethod

• 子类必须全部实现重写父类的abstractmethod方法
• 非abstractmethod方法可以不实现重写
• 带abstractmethod方法的类不能实例化

  from abc import abstractmethod, ABCMeta

 1 class BettingStrategy(metaclass=ABCMeta):

    @abstractmethod
    def bet(self):
        print('0')

    def record_win(self):
        print('win')

    def record_loss(self):
        print('loss')


class Bet(BettingStrategy):
    def bet(self):
        print('1')

扩展：abc模块

二、staticmethod：静态函数

对象不用实例化即可调用的函数

class Hand4:
    def __init__(self, dealer_card, *cards):
        self.dealer_card = dealer_card
        self.cards = cards

    @staticmethod
    def freeze(other):
        hand = Hand4(other.dealer_card, *other.cards)
        return hand

    @staticmethod
    def split(other, card0, card1):
        hand0 = Hand4(other.dealer_card, other.cards[0], card0)
        hand1 = Hand4(other.dealer_card, other.cards[1], card1)
        return hand0, hand1

    def __str__(self):
        return ','.join(map(str, self.cards))

h41 = Hand4(deck3.pop(), deck3.pop(), deck3.pop())
    s1, s2 = Hand4.split(h41, deck3.pop(), deck3.pop())
    s3 = Hand4.freeze(h41)