poython 不知哪里出错了？

[sayigood]

代码及提示如下：
>>> s
'asdfadsf'
>>> for i in [None] + range(-1, -len(s), -1):
... print (s[:i])
...
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: can only concatenate list (not "range") to list

非常感谢你的帮助。。。

[dskit]

s = 'asdfadsf'
for i in [None] + range(-1, -len(s), -1):
	print s[:i]

在python2.6下没有任何问题。

[dskit]

成功输出：
asdfadsf
asdfads
asdfad
asdfa
asdf
asd
as
a

[ermine]

Python3.0
>>> for i in [None]+range(-1,-len(s),-1):
print(s[:i])

[ermine]

点错键了。。。。
python3.0里，可以用list将range转换。
>>> for i in [None]+list(range(-1,-len(s),-1)):
print(s[:i])


asdfadsf
asdfads
asdfad
asdfa
asdf
asd
as
a

[goosman]

python 3之后, range返回的是range对象了.
在此之前的版本中, 楼主的代码执行是没有问题的.

[goosman]

The range type is an immutable sequence which is commonly used for looping. The advantage of the range
type is that an range object will always take the same amount of memory, no matter the size of the range it
represents. There are no consistent performance advantages.
Range objects have very little behavior: they only support indexing, iteration, and the len() function.

上面是3.1的library文档中对新的range类型的描述.
其仅支持索引, 迭代, len()几种有限的操作.

[Semigod]

range得到的结果并不是list，这一点你没有搞清楚
range()只是iterable object，并不是list

[sayigood]

这段代码是python核心编程中的一段：
用以实现将字符串s每次显示都把最后一个字符去掉
不知道该如何修改啊？谢谢

[sayigood]

Get it!
谢谢各位