切片插入问题，L[1:1]
练习一些Python，这是一种很容易掌握的语言。
我
>>> L = [1,2,3,4]
>>> L[1:1] = [1,2,3]
>>> L
[1, 1, 2, 3, 2, 3, 4]
在第二行实际上 L[1:1] 是空列表，但是 python 如何理解插入 [1,2,3] 列表从<代码>1。我猜有一些内部结构对我们来说不透明，显然，我猜 L[1:1] 返回对索引 1 的引用，即使它返回一个空列出...
最美好的祝愿， 乌穆特
practising some python, which is a pretty easy language to grab up.
I have
>>> L = [1,2,3,4]
>>> L[1:1] = [1,2,3]
>>> L
[1, 1, 2, 3, 2, 3, 4]
so on line two actually L[1:1] is empty list, but how can python understand that insert the [1,2,3] list to starting from 1. I guess there is some internals which is not transparent to us, here apparently, I guess L[1:1] returns a reference to index 1 even if that returns an empty list...
Best wishes,
Umut
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L[1:1]表示列表L的切片，从索引 1（第二个元素）开始，一直到但不包括索引 1。因此它是一个空列表。在作业的右侧，它只是一个匿名空列表。但在左侧，赋值知道切片是在哪里进行的，并且可以将新的列表值拼接到正确的位置。L[1:1]means the slice of the listLstarting at index 1 (the second element), up to but not including index 1. So it is an empty list. On the right-hand side of an assignment, it is simply an anonymous empty list. But on the left-hand side, the assignment knows where the slice has been made, and can splice in the new list value into the proper place.切片的行为有所不同，具体取决于它是在表达式的左侧还是右侧。当它位于左侧时，它不会返回列表 - 相反，它表现为切片对象，它了解有关切片的更多信息，并且专门重写了赋值以作为插入进行操作。
Slicing behaves differently depending on whether it's on the left- or right-hand side of an expression. When it's on the left side, it doesn't return a list - instead, it behaves as a slice object, which knows more about slices and has assignment specifically overridden to operate as insertion.
在我看来，官方的 Python 教程对此解释得最好。 第 3.1.2 章 的末尾有以下图表：
这说明了什么是你可以将索引视为指向元素之间。因此，在此图中，如果指定切片
[1:1]，则实际上指的是H和e之间的空格，但不是包括他们。如果您想覆盖
H和e，您可以指定切片[0:2]。The official Python Tutorial explains it best, in my opinion. The end of Chapter 3.1.2 has the following diagram:
What this illustrates is that you can think of the indices as pointing BETWEEN the elements. So in this illustration, if specifying a slice
[1:1], you are actually referring to the space betweenHande, but not including them.If you wanted to overwrite
Hande, you would specify the slice[0:2].