反转列表元组的顺序

I have a tuple ([1,2,3], [4,5,6]) and I want to reverse the list inside so that it becomes ([3,2,1],[6,5,4]) without having to create a new tuple and adding elements to it. The closest I've gotten is:

我有一个元组（[1,2,3]，[4,5,6]），我想反转里面的列表，使它成为（[3,2,1]，[6,5,4]）无需创建新元组并向其添加元素。我最接近的是：

my_func(....):
   for i in tuple(...):
     i = i[::-1]
   return tuple(....)

problem is that while i prints out what I want..the tuple was never changed

问题是，当我打印出我想要的东西时......元组从未改变过

2 个解决方案

#1

Tuples are immutable but the objects contained by them can be either mutable or immutable, so if we modify a mutable object contained by the tuple then the change will be reflected at all the references of that object, that includes the tuple as well.

元组是不可变的，但它们包含的对象可以是可变的或不可变的，因此如果我们修改元组包含的可变对象，那么更改将反映在该对象的所有引用上，包括元组。

As in this case we've lists, so, all we need to do is to loop over the tuple and call .reverse() on the lists.

在这种情况下，我们列出了，所以我们需要做的就是遍历元组并在列表上调用.reverse（）。

>>> t = ([1,2,3], [4,5,6])
>>> for x in t:
...     x.reverse()
...     
>>> t
([3, 2, 1], [6, 5, 4])

Another example:

另一个例子：

>>> x = [1, 2, 3]
>>> t = (x, 'abc')
>>> x.reverse()
>>> t
([3, 2, 1], 'abc')
>>> x
[3, 2, 1]

#2

As frostnational says, tuples are immutable, so you will have to create new ones.

正如霜冻所说，元组是不可改变的，所以你必须创造新元组。

You could do something like this:

你可以这样做：

>>> a = ([1,2,3],[4,5,6])
>>> b = map(lambda t: reversed(t), a)
>>> for sublist in b:
...     for item in sublist:
...         print(item)
... 
3
2
1
6
5
4

#1