title: c++:error C2440: '<function-style-cast>' : cannot convert from 'A<TYPE>' to 'B<TYPE>'
body: <p>I have a base class A and it has a subclass B.
  A overrides the + operator and B overrides it as well,calls the parent's +operator, and casts the result to B. Then I am getting the error message:</p>
  
  <blockquote>
    <p>error C2440: '' : cannot convert from 'A'
    to 'B'</p>
  </blockquote>
  
  <p>I thought polymorphism worked in a way that should allow this to work?</p>