Is the "=" operator overloaded for msg variables?

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Hi all,

I was worrying whether the "=" operator is systematically overloaded for objects of class sensor_msgs::JointState and other predefined messages in ROS. Up to now, I have programmed that "by hand" but it's a bit silly if the = operator is enough. That said, I do not know how to check that.

If it is the case for predefined messages, then is it also true when one defines their own message types (which I never had to do up to now, I must admit).

Thanks for any input.

        ggg