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property


ast wrote at 2020-6-26 09:02 +0200:
>Hello,
>
>I am wondering why this code is OK:
>
>class Temperature:
>     def __init__(self):
>	self.celsius = 0
>
>     fahrenheit = property()
>
>     @fahrenheit.getter
>     def fahrenheit(self):
>	return 9/5*self.celsius +32
>
>     @fahrenheit.setter
>     def fahrenheit(self, value):
>	self.celsius = (value-32)*5/9
>
>
>and this one is not:
>
>
>class Temperature:
>     def __init__(self):
>	self.celsius = 0
>
>     fahrenheit = property()
>
>     @fahrenheit.getter
>     def f(self):
>	return 9/5*self.celsius +32
>
>     @fahrenheit.setter
>     def f(self, value):
>	self.celsius = (value-32)*5/9

A decoration

  @dec...
  def f(...): ...

is a shorthand notation for

  def f(...): ...
  f = dec...(f)

In your first example, "fahrenheit" is defined as you expect.
In the second example, some property functions are bound to `f`.
It depends on implementation details, whether the final
`f` and/or `fahrenheit` has both getter/setter definitions.

Always use the same name for function and property (as you do in
your first class).