Python3基础 tuple(list) 改变list元素的内容时，元组的id值不变

 

•        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]: a = (1, 2, [4, 5])  # index=2的元素是list类型                                                 

In [2]: type(a), id(a)                                                          
Out[2]: (tuple, 140524432415480)

In [3]: a[2].append(6)  # 改变index=2的list类型的元素的值                                                        

In [4]: a                                                                       
Out[4]: (1, 2, [4, 5, 6])

In [5]: type(a), id(a)  # id(a)的值竟然无变化                                                       
Out[5]: (tuple, 140524432415480)

In [6]: exit                                                                    
(py37) coder@ubuntu:~$ conda deactivate
coder@ubuntu:~$ 

 

source_code

def id(*args, **kwargs): # real signature unknown
    """
    Return the identity of an object.
    
    This is guaranteed to be unique among simultaneously existing objects.
    (CPython uses the object's memory address.)
    """
    pass

 

reference

• https://blog.csdn.net/weixin_37641832/article/details/84332763

 

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

 

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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。