PyBindGen

Please, write example about operator=

Asked by steep8

I'm not found how to deal with "operator=", please write here example.

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Gustavo Carneiro
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Gustavo Carneiro (gjc) said : 		#1

PyBindGen doesn't support operator=, nor does it make sense.

Do you mean operator== ? operator== is used transparently, no need to do anything...

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steep8 (steep8) said : 		#2

I mean Test& operator=(const Test& right),
why it nor does make sense?
test = Test()
test2 = Test()
test2 = test work well without operator= ?

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Best Gustavo Carneiro (gjc) said : 		#3

The issue is that C/C++ and Python differ completely in this respect.

In Python, test2 and test are simply pointers, test2 = test simply makes test2 point to the same object that test points to.

In C++, "test2 = test" makes test2 a copy of the object contained in test.

PyBindGen has the CppClass.add_copy_constructor() method to tell it to generate code to support copy-constructor. This means that the class will have a constructor that takes another class as parameter, so you can write "test2 = Test(test1)", which creates a copy. In addition, this triggers a __copy__ method to be generated, allowing you to use the copy module: from copy import copy; test2 = copy(test1).

I'm not sure if operator= has any effect in pybindgen, to be honest. If you use gccxml scanning, pybindgen calls the type_traits.has_copy_constructor() function, which may or not take operator= into account, I don't know.

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steep8 (steep8) said : 		#4

Thanks Gustavo Carneiro, that solved my question.