Calling a derived class's constructor from a parent method

[jason]

On Wednesday, January 14, 2015 at 12:05:55 PM UTC-5, Mark Lawrence wrote:
 
> I'm confused, can you please explain what you're trying to achieve 
> rather than how you're trying to achieve it and I'm sure that others 
> will give better answers than I can :)
> 

Good call. Coming up with a minimal example make things pretty far out of context.

The base class represents a generic function (in formal logic) with some name and a list of parameters. The derived class is some sort of specialization of that generic class (like associative functions, etc).

It is desirable to do certain things to these functions, like perform substitution or canonization, that can be implemented in the basic class but which I'd like to return as a copy rather than modify the class. Thus, the base class needs to know which derived class (if any) to create.

The burden is indeed on me to keep the signature of the init() for each of these the same.