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POSetting a property inside a Python method
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copied!<p>I want to set a read-only attribute inside a class method.<br> I have already tried this:</p> <pre><code>class Foo(object): def __init__(self, v): self._set('_v', v) def _set(self, attr, v): setattr(self, attr, v) setattr(Foo, attr[1:], property(lambda self: getattr(self, attr))) </code></pre> <p>but it is horrible. Is there another way? What I need to do is setting the property:</p> <pre><code>class Foo(object): def __init__(self, v): self._v = v @ property def v(self): return self._v >>> f = Foo(42) >>> f.v 42 >>> f.v = 41 AttributeError: can't set attribute ## This is what I want: a read-only attribute </code></pre> <p>but I need to do it inside a method. Is there another way? </p> <p>Thank you,<br> rubik</p> <p>P.S. I have already checked this post, but it does not solve my problem: <a href="https://stackoverflow.com/questions/3302020/using-python-property-inside-a-method">Using Python property() inside a method</a></p> <p>EDIT: I cannot use <code>property</code>, because I want to set it inside a method. I can use <code>property</code> only from outside:</p> <pre><code>class Foo(object): def __init__(self, v): self._v = v @ property def v(self): return self._v ## ...OR def getv(self): return self._v v = property(getv) </code></pre> <p>And I can't do that because I don't know the property name and I have to set it dynamically. Something like this:</p> <pre><code>class Foo(object): def __init__(self, v): self._set_property_from_inside('v', v) >>> f = Foo(42) >>> f.v 42 </code></pre>

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