Python - Enums, dataclass

IntEnum

• IntEnum’s members are ints, while enum instance’s members are its own class
  • Enum: Base class for creating enumerated constants.
  • IntEnum: Base class for creating enumerated constants that are also subclasses of int.

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      class Shape(IntEnum):
          CIRCLE = 1
          SQUARE = 2
    
      class Color(Enum):
          RED = 1
          GREEN = 2
    
      Shape.CIRCLE == Color.RED
      >> False
    
      Shape.CIRCLE == 1
      >>True
    

  • Also, this would raise: ValueError: invalid literal for int() with base 10: 'a'

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      class State(IntEnum):
          READY = 'a'
          IN_PROGRESS = 'b'
          FINISHED = 'c'
          FAILED = 'd'
    

  • Create IntEnum instance with data:

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      self.motor_error_code = MotorErrorCode(self.motor_error_code)
    

Dataclass

The @dataclass(frozen=True) decorator defines a class whose instances are simple data containers with automatically generated methods. By using @dataclass, Python creates common methods such as __init__ (constructor), __repr__, and __eq__, eliminating the need to write boilerplate code manually.

The frozen=True argument makes instances of the class immutable, meaning that once an object is created, its fields cannot be modified.

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@dataclass(frozen=True) 
class Config:

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