Class Disposable

This class can be used for returning a value by copy. It relies on the returned object exposing a swap(T&) method through which the copy constructor and assignment operator are implemented, thus resulting in actual move semantics. Typical use of this class is along the following lines:

Disposable<Foo> bar(Integer i) {
    Foo f(i*2);
    return f;
}

warning In order to avoid copies in code such as shown above, the conversion from T to Disposable<T> is destructive, i.e., it does not preserve the state of the original object. Therefore, it is necessary for the developer to avoid code such as

Disposable<Foo> bar(Foo& f) {
    return f;
}

which would likely render the passed object unusable. The correct way to obtain the desired behavior would be:

Disposable<Foo> bar(Foo& f) {
    Foo temp = f;
    return temp;
}