Python 文化中的接口和协议

2018 PyCon 中国演讲 PPT

Transcript

1. 3\WKRQ෈۸Ӿጱളݗ޾ܐᦓ
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   By laixintao
   

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2. 
   Ø Luatable
   Ø C
   Ø Java ……
   Ø JavaScript!
   Ø Python
   __method__
   

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3. •
   • “”
   • “xxx”
   • Dunder method
   

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4. http://lucumr.pocoo.org/2011/7/9/python-and-pola/
   

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6. 
   
   
   ——Leonardo Rochael
   

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9. Python“”
   • Python “”
   •
   
   

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10. 
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11. 
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12. __init__
    __new__
    __del__
    https://www.python.org/download/releases/2.2/descrintro/#__new__
    

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13. __new__
    

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14. __new__
    

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15. 
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16. 
    https://www.python.org/dev/peps/pep-0207/
    https://docs.python.org/3/reference/expressions.html#value-comparisons
    
    obj1 __lt__x
    obj1 < x
    obj1.__lt__(x)
    x > obj1
    
    1. obj1 > x
    2. : obj1 < x
    3. :
    obj1.__lt__(x)
    

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17. @functools.total_ordering
    •
    
    •
    __eq__
    

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18. 
    
    https://github.com/zestyping/q/blob/master/q.py
    

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19. 
    • __pot__(self) +a
    • __add__(self, other) a + b
    •
    __add__(self, other) b + a
    • __iadd__(self, other)
    • __int__(self)
    https://docs.python.org/3/library/operator.html
    

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21. 
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22. 
    • __str__ str()
    
    • __repr__ repr()
    
    __str__
    • __bytes__ bytes()
    
    • __format__ format()
    
    • __dir__ dir()
    
    • __hash__ hash()
    
    https://dbader.org/blog/python-repr-vs-str
    

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23. format
    

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24. dir()
    https://github.com/laike9m/pdir2
    

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25. hash ()
    •
    •
    __eq__
    •
    __eq__ hashable
    https://www.kawabangga.com/posts/1821
    https://docs.python.org/3/reference/datamodel.html#object.__hash__
    

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26. 
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27. 
    __getattr__
    __setattr__
    __delattr__
    __getattribute__
    featurehttps://www.kawabangga.com/posts/2809
    
    
    

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28. 
    

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29. 
    https://docs.python.org/3/reference/datamodel.html#more-attribute-access-for-new-style-classes
    

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30. __setattr__
    

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31. 
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32. 
    
    • __len__() len() __bool__() return self.__len__()
    • __getitem__() obj[key]
    • __setitem__() obj[key] = value
    • __missing__() obj[non_exist]
    • __delitem__() del obj[key]
    • __iter__()
    • __reversed__() reversed()
    
    __getattr__
    __setattr__
    __delattr__
    __getattribute__
    []
    .
    
    

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33. Python
    Python forhttp://effbot.org/zone/python-for-statement.htm
    
    __getitem__()
    for
    

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34. 
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35. 
    • __instancecheck__(self, instance) isinstance(instance, class)
    • __subclasscheck__(self, subclass) issubclass(subclass, class)
    

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36. sized
    https://github.com/python/cpython/blob/9d4712bc8f26bf1d7e62
    6b53ab092fe030bcd68d/Lib/_collections_abc.py#L359
    

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37. 
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38. First Class Object
    •
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    •
    •
    
    https://dbader.org/blog/python-first-class-functions
    https://www.kawabangga.com/posts/2613
    

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39. 
    
    __call__()
    

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40. 
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    • (#
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41. 
    •
    
    • __enter__()
    • __exit__()
    https://www.kawabangga.com/posts/2010
    

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42. 
    print
    

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43. contextlib.contextmanager
    

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44. 
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45. @property
    https://www.kawabangga.com/posts/2302
    

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46. 
    

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47. ……
    •descr.__get__(self, obj, type=None) -> value
    •descr.__set__(self, obj, value) -> None
    •descr.__delete__(self, obj) -> None
    https://docs.python.org/3.7/howto/descriptor.html
    

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48. 
    ORM
    

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49. function
    method
    • method __dict__ function
    • function __get__()
    method
    https://docs.python.org/3.7/howto/descriptor.html#functions-and-methods
    

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50. 
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51. 
    • __copy__(self) copy.copy()
    • __deepcopy__(self, memodict={}) copy.deepcopy()
    

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52. pickle
    • object.__getnewargs_ex__()
    • object.__getnewargs__()
    • object.__getstate__()
    • object.__setstate__(state)
    • object.__reduce__()
    • object.__reduce_ex__(protocol)
    https://www.kawabangga.com/posts/2782
    

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53. @laixintao
    www.kawabangga.com
    SRE
    Python
    

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