Re: [Boost-users] [python] nested attributes, style question

Malte Clasen writes:

Hi,

let's say we've got the following C++ classes:

class position { public: float get_height() const; void set_height(float value); private: float height_; };

class object { public: position get_position() const; void set_position(const position& value); private: position pos_; };

This design is not fixed, but right now this is the starting point. When I added the boost.python interface to it using add_property(), I quickly noticed that using these classes feels somehow unpythonic: I cannot modify the height of the position of an object using

obj.pos.height = x

because get_position() returns the position by value, so the following set_height modifies a temporary instance of position. The work-around on the python side looks clumsy:

Is there a common solution to this problem? Does my proxy approach seem reasonable?

http://thread.gmane.org/gmane.comp.python.c++/8966 should help. Use return_internal_reference. -- Dave Abrahams Boost Consulting www.boost-consulting.com