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return "this" in C++?

In Java you can simply return this to get the current object. How do you do this in C++?

Java:

class MyClass {

    MyClass example() {
        return this;
    }
}
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Well, first off, you can't return anything from a void-returning function.

There are three ways to return something which provides access to the current object: by pointer, by reference, and by value.

class myclass {
public:
   // Return by pointer needs const and non-const versions
         myclass* ReturnPointerToCurrentObject()       { return this; }
   const myclass* ReturnPointerToCurrentObject() const { return this; }

   // Return by reference needs const and non-const versions
         myclass& ReturnReferenceToCurrentObject()       { return *this; }
   const myclass& ReturnReferenceToCurrentObject() const { return *this; }

   // Return by value only needs one version.
   myclass ReturnCopyOfCurrentObject() const { return *this; }
};

As indicated, each of the three ways returns the current object in slightly different form. Which one you use depends upon which form you need.


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