Should accessors return values or constant references?

Question

Suppose I have a class Foo with a std::string member str. What should get_str return?

std::string Foo::ge         


        

Answer 1

It depends on what you want to do with the return value.

This is better if you just want to make a query and not modify str.

const std::string& Foo::get_str() const
{
    return str;
}

Otherwise, go for this:

std::string& Foo::get_str()
{
    return str;
}

And if you want a copy/clone of str, then use this:

std::string Foo::get_str() const
{
    return str;
}