Am 16.10.2012 15:51 schrieb Pradipto Banerjee:
I am trying to define class, where if I use a statement a = b, then instead of "a" pointing to the
same instance as "b", it should point to a copy of "b", but I can't get it right.
This is not possible.
Currently, I have the following:
----
class myclass(object):
Myclass or MyClass, see http://www.python.org/dev/peps/pep-0008/.
def __eq__(self, other):
if instance(other, myclass):
return self == other.copy()
return NotImplemented
This redefines the == operator, not the = operator.
It is not possible to redefine =.
One way could be to override assignment of a class attribute. But this
won't be enough, I think.
Let me explain:
class MyContainer(object):
@property
def content(self):
return self._content
@content.setter
def content(self, new):
self._content = new.copy()
Then you can do:
a = MyClass()
b = MyContainer()
b.content = a
print b.content is a # should print False; untested...
But something like
a = MyClass()
b = a
will always lead to "b is a".
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What?
Thomas
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