> Does anyone know if it's possible to call a property setter inside of a
> class's init method? Below is a code sample of what I'm trying to do.
Just a quick guess:
> class Question(object);
replace the semi-colon with a colon (I assume it's just a typo, since you don't
get an error for this).
>
> def __init__(self, value):
> self.text(value)
self.text = value # is the way to do this, if you're using it as a
property.
>
> @property
> def text(self):
> return self._text
>
> @text.setter
> def text(self, value):
> if not isinstance(value, str):
> raise TypeError
> self._text = value
>
>
> Here's an explanation of what I'm trying to accomplish:
>
> I have a class with an init method that is getting bloated with
> error-checking guard clauses. I was hoping to "hide" some of these guard
> clauses by using the @property decorator and its associated setter method.
> I'd like to use the Question.text property to set the value (or raise an
> error) upon instantiation of a Question object. I figured this would clean up
> my init method and move the error-checking code closer to the relevant class
> attribute. I've tried numerous variations on the above init method, but all
> without success.
>
>
> In the current version, when I try:
>
> >>> q = Question("Hello world?")
>
> I get the following error:
>
> AttributeError: 'Question' object has no attribute '_text'
>
> I was hoping text property would create self._text for me on instantiation,
> but apparently no dice. I'm also getting errors when I do the below
> variations:
>
> ### variation 1 ####
> def __init__(self, value):
> self._text = ''
> self.text(value)
>
> ### variation 2 ####
> def __init__(self, value):
> self._text = None
> self.text(value)
>
> Can anyone point out what I'm doing wrong? I suspect I'm misunderstanding
> properties and/or the finer points of object instantiation. Any help would be
> greatly appreciated!
Again, see the correction above: use 'self.text = value'. Don't use self._text,
nor call self.text()
>
> Thanks!
> Serdar
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