1,iter(object)
例子:
lst = [1, 2, 3]
for i in iter(lst):
print(i)
2,iter(object, sentinel)
例子:
class counter:
def __init__(self, _start, _end):
self.start = _start
self.end = _end
def get_next(self):
s = self.start
if(self.start < self.end):
self.start += 1
print('----------',self.start)
print('++++++++++',self.end)
else:
print(self.start)
print(self.end)
raise StopIteration
return s
c = counter(1, 4)
iterator = iter(c.get_next, 5)#当返回值为5时抛出异常
print(type(iterator))
for i in iterator:
print('===================================',i)
运行结果如下:
C:\Users\snowshuang\AppData\Local\Programs\Python\Python37\python.exe C:/Users/snowshuang/PycharmProjects/logging/log1.py
<class ‘callable_iterator’>
———- 2
++++++++++ 4
=================================== 1
———- 3
++++++++++ 4
=================================== 2
———- 4
++++++++++ 4
=================================== 3
4
4