Deleting copy constructor breaks inherited constructors

Question

I am trying to use the constructor inheritance feature of C++11. The following snippet (copied from somewhere, I don\'t remember whence) works completely fine:

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Answer 1

The problem is that marking a copy constructor with delete makes it user-declared, which in effect deletes the default constructor of that class (in your case Derived). The behaviour can be seen in this simple code:

struct X
{
    X(const X&) = delete; // now the default constructor is not defined anymore
};

int main() 
{
    X x; // cannot construct X, default constructor is inaccessible 
}

As a side remark: even if Base::Base() would be inherited, the compiler would see it like Derived(): Base(){}. But Derived is deleted, so it cannot really call Base::Base(). In general, a using Base::Base statement is just syntactic sugar for the corresponding compiler-generated Derived(params): Base(params){}.