Using CRTP instead of standard polymorphism

[giacomo-b]

A Curiously Recurring Template Pattern (CRTP) would probably be a better design choice instead of classic inheritance that makes use of virtual functions.

Advantage in the case of, e.g. LinearSystem and NonlinearSystem (both of which are Systems):

1. There's need to replace System instances at runtime or to work with heterogeneous collections of Systems.
2. CRTP would be more flexible
3. Virtual methods imply vtable lookups at runtime. With CRTP the compiler knows which class gets instantiated, thus guaranteeing better performance.

[giacomo-b]

C++20 concepts would be even better.

[tomlankhorst]

Best of both worlds: Better Code: Runtime Polymorphism - Sean Parent

[giacomo-b]

Thank you Tom, I will watch it and elaborate on this.