Python 文化中的接口和协议

2018 PyCon 中国演讲 PPT

Transcript

1. 3\WKRQ෈۸Ӿጱളݗ޾ܐᦓ  Ӿࢵ Ӥၹ By laixintao
2. 
    Ø Lua
   table Ø C
    Ø Java
    …… Ø JavaScript
   ! Ø Python
     __method__
3. •  • “
   ” • “xxx” • Dunder method
4. http://lucumr.pocoo.org/2011/7/9/python-and-pola/
6.    
      ——Leonardo Rochael
9. Python“
   ” •    
   Python “” •  
10. 
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12. __init__ __new__ __del__ https://www.python.org/download/releases/2.2/descrintro/#__new__
13. __new__ 
    
14. __new__ 
    
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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)
17. @functools.total_ordering • 
      •  __eq__
18.    https://github.com/zestyping/q/blob/master/q.py
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
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
23. 
     format 
24. 
     dir() https://github.com/laike9m/pdir2
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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     __getattr__ __setattr__ __delattr__ __getattribute__   feature
    https://www.kawabangga.com/posts/2809 
28. 
    
29. 
    https://docs.python.org/3/reference/datamodel.html#more-attribute-access-for-new-style-classes
30. 
     __setattr__
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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__ []  . 
33. Python 
    Python forhttp://effbot.org/zone/python-for-statement.htm  __getitem__()
      for  
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35. 
    • __instancecheck__(self, instance) isinstance(instance, class) • __subclasscheck__(self, subclass) issubclass(subclass, class)
36.  sized 
     https://github.com/python/cpython/blob/9d4712bc8f26bf1d7e62 6b53ab092fe030bcd68d/Lib/_collections_abc.py#L359
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38. First Class Object •  
     •   •   •   
      https://dbader.org/blog/python-first-class-functions https://www.kawabangga.com/posts/2613
39.     __call__()
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41. 
      • 
      •   __enter__() •   __exit__() https://www.kawabangga.com/posts/2010
42.   print
43. contextlib.contextmanager
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45. @property   https://www.kawabangga.com/posts/2302
46. 
    
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
48.    ORM
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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51. 
    
    • __copy__(self)  copy.copy()  • __deepcopy__(self, memodict={}) 
    copy.deepcopy() 
52. pickle • object.__getnewargs_ex__() • object.__getnewargs__() • object.__getstate__() • object.__setstate__(state) • object.__reduce__() • object.__reduce_ex__(protocol) https://www.kawabangga.com/posts/2782
53. @laixintao www.kawabangga.com SRE  Python