关于iter()方法

hangfrieddays

想问关于iter方法的第二种使用，我以下的代码是否get到了精髓，或者说是多此一举呢

class Iter:
    def __init__(self):
        self.count = 0

    def __iter__(self):
        return self

    def __next__(self):
        self.count += 1
        if self.count > 3:
            raise StopIteration
        return self.count


a = Iter()
b = iter(a.__next__, 10)
print(next(b))

suchocolate

__next__里定死了3，外面用10没有意义。不如这样：

class Iter:
    def __init__(self, limit=1):
        self.count = 0
        self.limit = limit

    def __iter__(self):
        return self

    def __next__(self):
        self.count += 1
        if self.count > self.limit:
            raise StopIteration
        return self.count


a = Iter(3)
try:
    while True:
        print(next(a))
except Exception as e:
    print(e)
print('=' * 20)
a = Iter(10)
try:
    while True:
        print(next(a))
except Exception as e:
    print(e)