Python3基础 内置函数 id

Posted 2022-03-15 xingchuxin

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

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code

[email protected]:~$ source activate py37
(py37) [email protected]:~$ 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]: # 变量a引用了数字1，a指向1的地址                                        

In [2]: a = 1                                                                   

In [3]: id(a)                                                                   
Out[3]: 94869542450208

In [4]: b = a  # 变量b 赋值为 变量a                                             

In [5]: id(b)                                                                   
Out[5]: 94869542450208

In [6]: # 修改数据的引用。变量a引用了数字2，a指向2的地址                        

In [7]: a = 2                                                                   

In [8]: id(a)                                                                   
Out[8]: 94869542450240

In [9]: id(b)                                                                   
Out[9]: 94869542450208

In [10]: # 变量名相当于一个标签                                                 

In [11]: exit                                                                   
(py37) [email protected]:~$ conda deactivate
[email protected]:~$ 

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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

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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。