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POCompiler error when overriding virtual methods
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copied!<p>Using VC71 compiler and get compiler errors, that i don't understand. Here comes the example</p> <pre><code>class A { public: virtual int& myMethod() = 0; virtual const int& myMethod()const = 0; }; class B: public A { public: // generates: error C3241: 'const int &B::myMethod(void)' : this method was not introduced by 'A' virtual int& A::myMethod(); // error C2555: 'B::myMethod': overriding virtual function return type differs and is not covariant from 'A::myMethod' virtual const int& A::myMethod() const; }; </code></pre> <p>when i switch order of both method definitions in B then I see a different compiler error:</p> <pre><code>class B: public A { public: // error C3241: 'const int &B::myMethod(void)' : this method was not introduced by 'A' virtual const int& A::myMethod() const; // error C2556: 'int &B::myMethod(void)' : overloaded function differs only by return type from 'const int &B::myMethod(void)' // error C2373: 'B::myMethod' : redefinition; different type modifiers virtual int& A::myMethod(); // error C2555: 'B::myMethod': overriding virtual function return type differs and is not covariant from 'A::myMethod' }; </code></pre> <p>however, if I omit the <code>A::</code> stuff then i don't get any compiler error:</p> <pre><code>class B: public A { public: virtual int& myMethod(); virtual const int& myMethod() const; }; </code></pre> <p>So, what exactly does <code>A::</code> in front of my method names and why do i see these diverse compiler errors? Any explanation welcome!</p>

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