Adding overload operator == with enable_if

I have a working template class point with an overload for operator==.

Because of floating point comparison, I was trying to add a second overload with enable_if for floating point to use an almost equal function.

This is my attempt:

template<typename T>
class Point2D
{
public:
   Point2D(T x, T y);

   Point2D& operator= (const Point2D& point);
   bool     operator==(const Point2D& point) const;
   bool     operator!=(const Point2D& point) const;
}

template<typename T>
Point2D<T>::Point2D(T x, T y) : x_(x), y_(y)
{
}

template<typename T>
Point2D<T>& Point2D<T>::operator=(const Point2D& point)
{
   if(this != &point)
   {
      x_ = point.x_;
      y_ = point.y_;
   }

   return *this;
}

template<typename T>
bool Point2D<T>::operator==(const Point2D& point) const
{
   return (x_ == point.x_) && (y_ == point.y_);
}

template<typename T>
typename std::enable_if<std::is_floating_point<T>::value, bool>::type
Point2D<T>::operator==(const Point2D& point) const
{
   return Traits::almost_equal(x_, point.x_) &&
          Traits::almost_equal(y_, point.y_);
}

Note:

• This is a semplified example.

• The code actually work without the enable_if overload

• I have to separate declaration and implementation (both in .h), so please refer to the code as is.

The error the compiler gives me is

error: prototype for 'typename std::enable_if::value, bool>::type Point2D::operator==(const Point2D&) const' does not match any in class Point2D' Point2D::operator==(const Point2D& point) const ^

error: candidate is: bool Point2D::operator==(const Point2D&) const bool Point2D::operator==(const Point2D& point) const ^

I don't understand what the error is referred to.