Question

f = (3, 4, 5, {3: 4}, [16, 7, 8])
g = (1, 2, [3, 4, [5, 6], {7: 8}], 9, 10, {11: f}, {12: [1, 2, {3, 4}, [5, 6]]})

我试图以g递归迭代。

如何在python中递归迭代每个元素，它适用于任何嵌套级别的列表？

我尝试使用hasattr，__iter__但不适用于未知级别的嵌套。

f=(3,4,5,{3:4},[6,7,8])
g = (1, 2, [3, 4, [5, 6], {7: 8}], 9, 10, {11: (3, 4, 5, {3: 4}, [16, 7, 8])}, {12: [1, 2, set([3, 4]), [5, 6]]})
print g
for each in g:
    print each
    try:
        if hasattr(each,"__iter__"):
            for ind in each:
                print ind
                if hasattr(ind,"__iter__"):
                    for ind1 in ind:
                        print ind1

Answer 1

要递归迭代某些东西，你当然需要一个递归函数。这是一个可以下载到list，tuple，set，frozenset和值的{{{ 1}}秒。它返回一个平面生成器，您可以在其中轻松迭代单个dictionary循环：

for

以下是您将如何使用该功能：

def recursive_iterator(iterable):
    for item in iterable:

        # directly iterable types:
        if type(item) in (list, tuple, set, frozenset):
            for child_item in recursive_iterator(item):
                yield child_item

        # other iterable types where we do not want to iterate over the item directly:
        elif type(item) in (dict,):
            for child_item in recursive_iterator(item.values()):
                yield child_item

        # not iterable types which we want to return as they are:
        else: 
            yield item

输出将是：

f = (3, 4, 5, {3: 4}, [16, 7, 8])
g = (1, 2, [3, 4, [5, 6], {7: 8}], 9, 10, {11: f}, {12: [1, 2, {3, 4}, [5, 6]]})

for x in recursive_iterator(g):
    print(x, end=" ")

See this code running on ideone.com

如何在python 2中详尽地进行迭代？

1 个答案: