◄Up► ◄Contents► ◄Index► ◄Back► ──────────────────────────────────────────────────────────────────────────── Compiler error C2500 'identifier1' : 'identifier2' is already a direct base class The specified class (or structure) appeared more than once in a list of base classes for a derived class. A class is called a direct base if it is mentioned in the base list. A class is called an indirect base if it is not a direct base but is a base class of one of the classes mentioned in the base list. A class cannot be specifed as a direct base class more than once. A class can be used as an indirect base class more than once. The following is an example of this error: class A { }; class B : public A, public A { }; // error class C : public A { }; class D : public A { }; class E : public C, public D { }; // OK, contains two As -♦-