I’m toying around with an API design and I’d really like to support + for concatenation between two generic types.

public class Query<T>
{
    public static Query<S> operator+ <R, S>(Query<T> q, SomeOtherObject<R> s) where R : ...
                                  // ^ C# compiler doesn't allow this
}

Is this possible with some other syntax I’m not getting right?