Python使用生成器函数实现可迭代对象

# 使用生成器函数实现可迭代对象
from mrjob.py2 import xrange


def f():
    print('in f(), 1')
    yield 1
    print('in f(), 2')
    yield 2
    print('in f(), 3')
    yield 3


g = f()
# print(g.__next__())
# print(g.__next__())
# print(g.__next__())
# print(g.__next__())

for x in g:
    print(x)

print(g.__iter__() is g)


class PrimeNumbers:
    def __init__(self, start, end):
        self.start = start
        self.end = end

    def isPrimeNum(self, k):
        if k < 2:
            return False
        for i in xrange(2, k):
            if k % i == 0:
                return False
        return True

    def __iter__(self):
        for k in xrange(self.start, self.end + 1):
            if self.isPrimeNum(k):
                yield k


for x in PrimeNumbers(1, 100):
    print(x)