Python缩进之谜

时间:2015-02-15 10:52:16

标签: python loops enter

为什么我收到以下错误?最后一个print语句不应该是while循环的一部分。

>>> while n>= 0:
...     n = n-1
...     print(n)
... print ("TO A!!")
  File "<stdin>", line 4
    print ("TO A!!")
        ^
SyntaxError: invalid syntax

3 个答案:

答案 0 :(得分:13)

您需要在while循环后按 enter 退出循环

>>> n = 3
>>> while n>=0:
...     n = n-1
...     print (n)
...                         # Press enter here
2
1
0
-1
>>> print ("To A!!")
To A!!

注意: - ...表示您仍然在while区块

答案 1 :(得分:4)

默认的python shell可以正常输入,但它确实无法理解从剪贴板粘贴。真正的解决方案是安装ipython,这是python的高级shell,有许多细节:

% ipython3
Python 3.4.2 (default, Oct  8 2014, 13:08:17) 
Type "copyright", "credits" or "license" for more information.

IPython 2.3.0 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.

In [1]: n = 5

In [2]: while n >= 0:
   ...:     n = n-1
   ...:     print(n)
   ...: print ("TO A!!")
   ...: 
4
3
2
1
0
-1
TO A!!

In [3]: 

答案 2 :(得分:3)

我猜错误出现了,因为python shell不支持。它希望你一次做一件事。我在python 2.7 shell中做了同样的事情,它说:

File "<pyshell#4>", line 4
    print 'to all'
                 ^
IndentationError: unindent does not match any outer indentation level

当我在我的python 3.4 shell中做同样的事情时,它说:unexpected indent.