《Effective C++》Item 45-46

member function templates

 

template<typename T>
class SmartPtr {
public:
  template<typename U> // member template
  SmartPtr(const SmartPtr<U>& other); // for a "generalized
  ... // copy constructor"
};

generalized copy constructors.

 

implicit type conversion functions are never considered during template argument deduction

As a declared function (not a function template), compilers can use implicit conversion functions (such as Rational's non-explicit constructor) when calling it

Inside a class template, the name of the template can be used as shorthand for the template and its parameters, so inside Rational, we can just write Rational instead of Rational.

The only way to declare a non-member function inside a class is to make it a friend.