C++ How to Program, 10/e

17.7 Constructors, Destructors and Exception Handling

First, let’s discuss an issue that we’ve mentioned but not yet resolved satisfactorily: What happens when an error is detected in a constructor? For example, how should an object’s constructor respond when it receives invalid data? Because the constructor cannot return a value to indicate an error, we must choose an alternative means of indicating that the object has not been constructed properly. One scheme is to return the improperly constructed object and hope that anyone using it would make appropriate tests to determine that it’s in an inconsistent state. Another scheme is to set some variable outside the constructor. The preferred alternative is to require the constructor to throw