发布-订阅模式实现示例

class PubSub:
    def __init__(self):
        self.subscribers = {}
    
    def subscribe(self, topic, callback):
        if topic not in self.subscribers:
            self.subscribers[topic] = []
        self.subscribers[topic].append(callback)
    
    def publish(self, topic, message):
        if topic in self.subscribers:
            for callback in self.subscribers[topic]:
                callback(message)

# 使用示例
pubsub = PubSub()

# 订阅者
def subscriber1(message):
    print(f"订阅者1收到: {message}")

def subscriber2(message):
    print(f"订阅者2收到: {message}")

pubsub.subscribe("news", subscriber1)
pubsub.subscribe("news", subscriber2)
pubsub.subscribe("weather", subscriber2)

# 发布者
pubsub.publish("news", "今日头条新闻")
pubsub.publish("weather", "明天晴天")