Python3基础 list dict set 均为unhashable type

  •        Python : 3.7.3
  •          OS : Ubuntu 18.04.2 LTS
  •         IDE : pycharm-community-2019.1.3
  •       Conda : 4.7.5
  •    typesetting : Markdown

code

coder@ubuntu:~$ source activate py37
(py37) coder@ubuntu:~$ ipython
Python 3.7.3 (default, Mar 27 2019, 22:11:17) 
Type 'copyright', 'credits' or 'license' for more information
IPython 7.5.0 -- An enhanced Interactive Python. Type '?' for help.

In [1]: hash(list())                                                            
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-1-3e2eb619e4e4> in <module>
----> 1 hash(list())

TypeError: unhashable type: 'list'

In [2]: hash(dict())                                                            
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-2-7762fff637c6> in <module>
----> 1 hash(dict())

TypeError: unhashable type: 'dict'

In [3]: hash(set())                                                             
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-3-2699417ebeac> in <module>
----> 1 hash(set())

TypeError: unhashable type: 'set'

In [4]: exit                                                                    
(py37) coder@ubuntu:~$ conda deactivate
coder@ubuntu:~$ 

source_code

def hash(*args, **kwargs): # real signature unknown
    """
    Return the hash value for the given object.
    
    Two objects that compare equal must also have the same hash value, but the
    reverse is not necessarily true.
    """
    pass

reference

resource

  • [文档 - English] docs.python.org/3
  • [文档 - 中文] docs.python.org/zh-cn/3
  • [规范] www.python.org/dev/peps/pep-0008
  • [规范] zh-google-styleguide.readthedocs.io/en/latest/google-python-styleguide/python_language_rules
  • [源码] www.python.org/downloads/source
  • [ PEP ] www.python.org/dev/peps
  • [平台] www.cnblogs.com
  • [平台] gitee.com


Python具有开源、跨平台、解释型、交互式等特性,值得学习。
Python的设计哲学:优雅,明确,简单。提倡用一种方法,最好是只有一种方法来做一件事。
代码的书写要遵守规范,这样有助于沟通和理解。
每种语言都有独特的思想,初学者需要转变思维、踏实践行、坚持积累。

posted @ 2019-07-06 21:05  行初心  阅读(1229)  评论(0编辑  收藏  举报