Question

I am am wondering how to create properly properties in C++. In Objective C, I use “@property” (in general with the (nonatomic, retain) attributes).

What is the proper way in C++ ?

Thanks !!

Answer 1

As Seva said, there are no properties in that kind of sense in C++. What you could do: write a class with a boost::share_ptr member variable, and optionally write getter and setter for that member. But that isn’t even really necessary, although maybe deemed good behaviour.

typedef boost::shared_ptr<std::string> StringPtrT;

class A {
public:
    void setStringProperty(StringPtrT s) { this->string_property = s; }
    StringPtrT getStringProperty() const { return this->string_property; }

protected:
    StringPtrT string_property;
}

The shared pointer will deal with the sharing and reference counting, basically simulating some kind of “retain” behaviour. IIRC boost shared_ptr types are always atomic, when it comes to updateing the reference counts. However, access to the object itself (de-referencing the pointer) will be non-atomic. You will have to deal with that yourself, if needed.