[fpc-devel] class abstract, class sealed implementation. please review.

[Thaddy]

AFAIK the rationale for a sealed class is that it can not be extended. 
In big shops that has an advantage in maintaining code. Also third 
parties can "lock" their code.

f.e.:

TDoNotTouchMe =  class sealed (TMyTouchableClass);

Means that if you use the former you cannot break code, if you use the 
latter (the parent) you can still extend your hierarchy.
Correct me if we are wrong ;)

We use it a lot after codereview and final checkin the production branches.
For us it means: "you must have a very good reason to touch it"