Does it make sense to provide non-const reference getter

Question

Sometimes I need to expose some of the class members. For example in the following example class Mechanic may need direct access to Engine componen

Answer 1

They can be useful when the value you are returning is actually on the heap.

template class Singleton
{
private:
    static T* m_pSingleton;

public:
    T& getSingleton() { assert(m_pSingleton); return(*m_pSingleton); };

}; // eo class Singleton