python基础-第六篇-6.1生成器与迭代器

names = iter([‘alex‘,‘wupeiqi‘,‘eva‘])
print(names)
print(names.__next__())
print(names.__next__())
print(names.__next__())
#在往下取就报错
# print(names.__next__())

#ATM
def cash_money(amount):
    while amount > 0:
        amount -= 100
        yield 100
        print(‘又来取钱啦！‘)

#这里没有真正执行函数，只是把函数变成一个迭代器
atm = cash_money(500)
# print(atm)
print(atm.__next__())
print(atm.__next__())
print(‘叫个大保健‘)
print(atm.__next__())

#消费者生产者模型

import time
def consumer(name1):
    print(‘{name}准备吃包子啦！‘.format(name = name1))
    while True:
        baozi = yield
        print(‘第{baozi_num}个包子来了，被{name}吃了！‘.format(baozi_num=baozi,name=name1))

def producer(name2):
    c = consumer(‘a‘)
    c2 = consumer(‘b‘)
    c.__next__()
    c2.__next__()
    print(‘{name}开始准备做包子啦！‘.format(name=name2))
    for i in range(1,6):
        time.sleep(1)
        print(‘做了两个包子！‘)
        c.send(i)
        c2.send(i)

producer(‘alex‘)

#列表解析
li = [i+100 for i in range(10)]
print(li)

#加条件
li2 = [i+100 for i in range(10) if i % 2 == 0]
print(li2)

#生成器表达式
li = (i+100 for i in range(10))
print(li)
#<generator object <genexpr> at 0x0000000000A2AE08>

#加条件
li2 = (i+100 for i in range(10) if i % 2 == 0)
for x in li2:
    print(x)