No type named 'type' in CTRP derived class

Question

I\'ve been experimenting with the Curiously Recurring Template Pattern for a generic single-argument functor and have two implementations: one using a template template para

Answer 1

Your code could be simplified to

template class
Base
{
    using Ftype = typename TDerived::type;
};

template class
Derived: public Base>
{
    using type = T;
};

Derived wat;

It does not work because at the point of Base instantiation Derived class is not complete, and compiler is not aware of Derived::type existence yet.