python3内置函数大全(python reversed函数返回值)

返回一个反转的迭代器。

>>> help(reversed)

Help on class reversed in module builtins:

class reversed(object)
 |  ## 使用方法：
 |  reversed(sequence, /)
 |  
 |  Return a reverse iterator over the values of the given sequence.
 |  
 |  Methods defined here:
 |  
 |  __getattribute__(self, name, /)
 |      Return getattr(self, name).
 |  
 |  __iter__(self, /)
 |      Implement iter(self).
 |  
 |  __length_hint__(...)
 |      Private method returning an estimate of len(list(it)).
 |  
 |  __next__(self, /)
 |      Implement next(self).
 |  
 |  __reduce__(...)
 |      Return state information for pickling.
 |  
 |  __setstate__(...)
 |      Set state information for unpickling.
 |  
 |  ----------------------------------------------------------------------
 |  Static methods defined here:
 |  
 |  __new__(*args, **kwargs) from builtins.type
 |      Create and return a new object.  See help(type) for accurate signature.

示例1.

>>> a = [0,1,2,3,4]
>>> a = reversed(a)
>>> next(a), next(a)

# output:
(4, 3)

示例2.

>>> a = 'hello world!'
>>> a = reversed(a)
>>> list(a)

['!', 'd', 'l', 'r', 'o', 'w', ' ', 'o', 'l', 'l', 'e', 'h']