Question

我对这段代码感到沮丧，我读过一些文章，但似乎我没弄明白：

class c:
def __init__(self):
    self.k = [9, 8]
def a(x):
    k = c()
    x = k.k

l = [1, 9]
a(l)

print l # expects [9, 8], got [1, 9]

更新，我发现了一种相当流氓的方式：

class c:
    def __init__(self):
        self.k = [9, 8]
def a(x):
    k = c()
    for i in reversed(x):
        x.remove(i)
    for i in k.k:
         x.append(i)


l = [1, 9]
a(l)

print l # output [9, 8]

Answer 1

我很难说出尝试要做什么。让我做一些假设并指出一些事情。

您的更正代码：

class C:     # by convention, Python classes are capitalized...
    def __init__(self):
        self.k = 10       
    def a(self, x):       # you need 'self' to refer to what instance
        x[1] = self.k

现在你可以做我想做的事情：

>>> c=C()          # you need an instance of that object
>>> li=[1,2]
>>> c.a(li)
>>> li
[1, 10]

属性k与c具有相同的范围，因此如果您希望.k为全局，请c全局：

>>> c.k
10
>>> c.k=22
>>> c.k
22

复制列表里面的函数python

1 个答案: