Python之路----生成器函数进阶

def generator():
        print(123)
        yield 1
        print(456)
        yield 2

g = generator()
ret = g.__next__()
print('***'ret)
ret = g.send(None)  #send 效果和 next一样
print('***'ret)

next与send

归纳：

1.send 获取下一个值得效果和next基本一致
2.只是在获取下一个值得时候，给上一个yield的位置传一个参数

使用send的注意事项

1.第一次使用生成器的时候，必须使用next获取一个值
2.最后一个yield不能接受外部的值

def average()
    sum = 0
    count = 0
    avg = 0
    while 1:
        num = yield avg
        sum += num
        count += 1
        avg = sum / count

avg_g = average()
avg_g.__next__()
avg1 = avg_g.send(10)
print(avg1)

获取移动平均值：

def init(func):
    def inner(*args, **kwargs):
        ret = func(*args, **kwargs)
        g.__next__()
        return g

    return inner

@init
def average():
    sum = 0
    count = 0
    avg = 0
    while 1:
        num = yield avg
        sum += num
        count += 1
        avg = sum / count

g = average()
avg1 = g.send(10)
print(avg1)

预激生成器的装饰器

python3.X----->yield from

def generator():
    a = ''
    b = 'abc'
    for i in a:
        yield i
    for i in b:
        yield i

g = generator()
for i in g:
    print(i)

原方法

def generator():
    a = ''
    b = 'abc'
    yield from a
    yield from b

g = generator()
for i in g:
    print(i)

yield from方法: