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    <p>Constness of a member function should be decided based on the question: <strong>is the member function used in a context to modify the object?</strong> (either the member modifies the object directly, or returns a reference/pointer to internal data so that outside callers can modify the object). If yes, make it non-const, otherwise make it const. </p> <p>The compiler will correctly choose between overloads that differ on constness alone. However, <strong>the return type is not used in overload resolution.</strong> Furthermore, the return by-value/by-reference should be decided only on the expected cost and the intended ownership of what you are going to return. Fortunately, C++11 makes life easier by providing <a href="https://stackoverflow.com/questions/3106110/what-are-move-semantics">move semantics</a>. This means that you can happily return large data structures by-value. Only return by reference if the referenced object will outlive the outside caller. </p> <p>It seems to me that your <code>int&amp; get()</code> should be renamed <code>void set(int)</code> and that you could split your <code>int get() const</code> into a computation helper and a proper <code>get()</code></p> <pre><code>class C { int val_; public: void modify() { /* some expensive computation on val_ */ } int get() const { return val_; } void set(int v) { val_ = v_; } }; </code></pre> <p>Alternatively, if you want to keep to <code>get()</code> functions, you could do</p> <pre><code>class D { int val_; public: void modify() { /* some expensive computation on val_ */ } int get() const { modify(); return val_; } int&amp; get() { modify(); return val_; } // no const-cast needed }; </code></pre>
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    1. POoverloaded const and non-const class methods returning references in C++
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    1. COMaybe my code was too minimal. Imagine get() is really get(string) and there is a lot of (potentially recursive) computation that is done with the string to determine exactly which object to return. I am looking to return a reference to the (public) member object but also be able to call the same (or overloaded) method from a const method.
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    2. CO@Johann same thing: write a helper function that does the computation, and write 2 `get()` functions to return the object state that each call the internal computation helper.
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