> ... a quaternion that can print itself as either 4 numbers (raw) or 3 numbers (euler angles). Then at last you presumably have overloads that are descriptive

> ... a quaternion that can print itself as either 4 numbers (raw) or 3 numbers (euler angles). Then at last you presumably have overloads that are descriptive, such as .ToRawString() and .ToEulerString(), correct? If you did a cout<<q, which one are you going to get? Having a non-abstract base .ToString() defined in Object (and that requires no format parameters) causes the issues. Of course you could define an enum and take it as a format, like .ToString(Format.Euler), but even if you define well-named overloads, the other .ToString() is still hanging there and probably doesn't do anything useful. So, for most cases in most current language, my statement was probably a bit strong and should be weakened to "the framework should not assume there is one best/default way to render any Object to a string regardless of context and purpose and offer a default implementation at the top of the hierarchy". Ultimately, however, I think the stronger argument does hold, but is not easily addressed in most languages, or at least is not addressed in any consistent to concise way across many languages.