Overloading assignment operator in a class template that can cast to another template type

Question

#ifndef NUMBER_HPP
#define NUMBER_HPP

template 
class Number
{
public:
  Number( T value ) : m_value( value )
  {
  }

  T value() const
  {
    retu         


        

Answer 1

You should do this:

template 
Number& operator=( const Number& number )
{
    m_value = number.value();
    return *this;
}

That is, use T2 in the parameter type, not in the return type!

I would rather use different letter for template parameter:

template 
Number& operator=( const Number& number )
{
    m_value = number.m_value; //I would also directly access the member variable!
    return *this;
}

I think, it is better to use explicit cast, if you want to use class type as template argument and whose constructor has been declared explicit:

 m_value = static_cast(number.m_value); 

---

By the way, the other operator= should be implemented as:

Number& operator=(T const & value ) //accept by const reference
{
    m_value = value;
    return *this; //you've to return!
}