In Oop

In OOP Code

items can have their operations, __add__ == ( + ) have their operations of arithmatic assignments __iadd__ == ( += ) and If one of those methods does not support the operation with the supplied arguments, it should return NotImplemented == __radd__.

• __add__ == ( + ) __add__
• __sub__ == ( - )
• __mul__ == ( * )
• __matmul__ == ( @ )
• __truediv__ == ( \ )
• __floordiv__ == ( \\ )
• __mod__ == ( % )
• __divmod__ == divmod()
• __pow__ == ( ** )
• __lshift__ == ( << )
• __rshift__ == ( >> )
• __and__ == ( & )
• __xor__ == ( ^ )
• __or__ == ( | )
• __lt__ == ( < )
• __le__ == ( <= )
• __eq__ == ( == )
• __ne__ == ( != )
• __gt__ == ( > )
• __ge__ == ( >= )
• __neg__ == ( - )
• __pos__ == ( + )
• __abs__ == abs()
• __invert__ == ( ~ )
• __complex__ == complex()
• __int__ == int()
• __float__ == float()
• __index__ https://docs.python.org/3/reference/datamodel.html#object.__index__
• __round__ == round()
• __trunc__ == math.trunc()
• __floor__ == math.floor()
• __ceil__ == math.ceil()
• Dictionary Dunders
  • __setitem__ When assigning values in a dictionary
  • __getitem__ Executed when we run the dict['key'] type of operation
  • __delitem__ ran when deleting a dictionary value del dict['key']
  • __contains__ Executed when we run the in operator if item in class_instance:
  • __len__ Is called if we ran a len() operation on our class instance
• __call__ if instance = Class() then __call__ is ran when we do: instance() right after
• __init__ init function is run as soon as a class instance is generated. It's the constructor.
• __post_init__ used in Data Classes for after __init__ as thats overwritten by data class
• __getattr__ Called when the default attribute access fails with an AttributeError
• __getattribute__ Called unconditionally to implement attribute accesses for instances of the class.
  • If the class also defines __getattr__(), the latter will not be called unless
    • __getattribute__() either calls it explicitly or raises an AttributeError.
• __setattr__ Called when an attribute assignment is attempted.
  • This is called instead of the normal mechanism (i.e. store the value in the instance dictionary).
• __delattr__ Like __setattr__() but for attribute deletion instead of assignment.
  • This should only be implemented if del obj.name is meaningful for the object.
• __dir__ Called when dir() is called on the object. A sequence must be returned.
  • dir() converts the returned sequence to a list and sorts it.
• __format__ when the class is being formatted in an fstring for with .format()
• __bool__ https://docs.python.org/3/reference/datamodel.html#object.__bool__
• __del__ The destructor of the class and what runs when attempting to del instance
• __bytes__ Computes a byte-string representation of an object. This should return a bytes object.
• __format__ produces a “formatted” string representation of an object.
• __hash__ https://docs.python.org/3/reference/datamodel.html#object.__hash__
• __repr__ Returns a representation of an object instance as a string __repr__
• __str__ when not defined it calls __repr__ by default to represent the instance as a string __str__
• __unicode__ New preferred method compared to __str__ in python 2
  • Python 3 uses unicode and therefore defaults to the __str__ method
• __enter__ Enter the runtime context related to this object using the with statement
• __exit__ Exit the runtime context related to this object
• __reversed__ not used with slice [::-1] but rather with reversed()
• __slots__ https://medium.com/@stephenjayakar/a-quick-dive-into-pythons-slots-72cdc2d334e

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Children

1. Dictionary Dunders
2. __add__
3. __new__
4. __repr__
5. __str__