Python中的可重用对象

有些类的实例在Python中是可移植的，但只有dunder “iter（）”方法，而不是“下一步（）”

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您的

\uu iter\uu

方法正在使用

下一个
函数返回一个对象：

z = Vector2d(4, 5)

z_iter = z.__iter__()

print(type(z_iter))

for coord in z:
    print(coord)

# <type 'generator'>

这确实提供了本机迭代功能——同样是以一种非常愚蠢的方式

编辑：在较旧的python 2.x版本中，将
next（）
替换为
\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu。我忘了具体是哪个了。
你的问题是什么？通过
\uuuuuu iter\uuuu
返回的生成器对象确实有一个
\uuuu next\uuuu
方法。是的。因为所有的iterables都有一个
\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
方法，但只有迭代器有一个
\uuuuu。因此，遵循最佳实践，您将拥有
ContainerClass
和
ContainerIterator
，这是许多样板文件，这是生成器的一大优点，它们让我们可以方便地生成迭代器，而不需要单独的类！我在报告中详细阐述了这一点
z = Vector2d(4, 5)

z_iter = z.__iter__()

print(type(z_iter))

for coord in z:
    print(coord)

# <type 'generator'>

class Vector2d:
    def __init__(self, x, y):
        self.x = float(x)
        self.y = float(y)
        self.index = 0

    def __iter__(self):
        return self

    def next(self):
        if self.index < 2:
            ret = [self.x, self.y][self.index]
            self.index += 1
            return ret
        else:
            raise StopIteration()


v = Vector2d(1, 2)
for coord in v:
    print(coord)