python3 生成器&迭代器

#Author by Andy#_*_ coding:utf-8 _*_import timefrom collections import Iterable#列表生成式

def func():    list=[]    for i in range(10000000):        list.append(i)    print(list)#print(list)#[0, 2, 4, 6, 8, 10, 12, 14, 16, 18]generator=(i for i in range(10))

#print(type(generator))def func1():    for i in generator:        print(i)def timmer():    time_start=time.time()    func1()    time_stop=time.time()    print(time_stop-time_start)#定义斐波那契数列def fib(max):    n,a,b=0,0,1    while n < max:        print(b)        a,b=b,a+b        n=n+1fib(10)# 注意，赋值语句：# a, b = b, a + b# 相当于：# t = (b, a + b)  # t是一个tuple# a = t[0]# b = t[1]def fib(max):    n,a,b=0,0,1    while n < max:        yield b        a,b=b,a+b        n=n+1    return ‘done‘f=fib(10)s=‘我是分割线‘print(f.__next__())print(s.center(50,‘-‘))print(f.__next__())print(s.center(50,‘-‘))#异常捕获g=fib(10)while True:    try:        x = next(g)        print(x)    except StopIteration as e:        print("Generator got en error:",e.value)        break##############################################################通过yield实现在单线程的情况下实现并发运算的效果def consumer(name):    print(‘%s 准备买面包啦‘%name)    while True:        product=yield        print(‘%s 买了面包%s‘%(name,product))def producer():    c1=consumer(‘韩梅梅‘)    c2=consumer(‘李雷‘)    c1.__next__()    c2.__next__()    for i in range(10):        time.sleep(1)        print(‘面包%s和面包%s出炉了！‘%(i,i+1))        c1.send(i)        c2.send(i+1)#producer()

# 迭代器# 可以被next()函数调用并不断返回下一个值的对象称为迭代器：Iterator。# # isinstance()判断一个对象是否是Iterable对对象# 生成器都是Iterator对象，但list、dict、str虽然是Iterable，却不是Iterator。# 把list、dict、str等Iterable变成Iterator可以使用iter()函数

print(isinstance(generator,Iterable))#True