问题描述
假设我有这些任务:
points = []
point = (1, 2)
我怎么会这样做:
points += point
它工作得很好,并且给了我点 = [1, 2].但是,如果我这样做:
It works completely fine, and gives me points = [1, 2]. However, If I do something like:
points = points + point
它给了我一个 TypeError: can only concatenate list (not "tuple") to list.不过,这些陈述不是一回事吗?
It gives me a TypeError: can only concatenate list (not "tuple") to list. Aren't these statements the same thing, though?
推荐答案
不同的是,list +=
等价于list.extend()
,取任何可迭代并扩展列表,它作为元组工作是可迭代的.(并就地扩展列表).
The difference, is that list +=
is equivalent to list.extend()
, which takes any iterable and extends the list, it works as a tuple is an iterable. (And extends the list in-place).
另一方面,第二个将一个新列表分配给 points
,并尝试将一个列表连接到一个元组,但由于不清楚预期结果是什么(列表或元组?).
On the other hand, the second assigns a new list to points
, and attempts to concatenate a list to a tuple, which isn't done as it's unclear what the expected results is (list or tuple?).
这篇关于列表 += 元组与列表 = 列表 + 元组的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持编程学习网!