Re^2: A class that cannot be subclassed.

Our coding standards say to prefer composition over subclassing. There's a brief summary of some of the arguments at Consider composition instead of subclassing. I don't see that as a reason to be hostile to the practice to the point of taking steps to prevent it, but this might not have been a general situation either. I suppose there could be a class that the author knows would break if subclassed. In that case, it might make sense to try to force that not to happen.

Comment on Re^2: A class that cannot be subclassed.

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Re^3: A class that cannot be subclassed. (direct) by tye (Sage) on Feb 28, 2008 at 05:20 UTC
The original node made me think of "I need a class that can't be used on Tuesdays. I could just check localtime in new(), but somebody could intentionally set their computer's clock wrong..." I suppose there could be a class that the author knows would break if subclassed. If that were the case, then I would put the checking at/around the point that I thought would break if it was subclassed. I wouldn't go the indirect route and try to prevent all forms of subclassing. And this would also avoid the obvious and wise questioning of "why do you want to make subclassing fatal?". I would also question a conclusion so broad as "this will break if subclassed". I expect such would more correctly be stated as "this will likely break if subclassed in the obvious way". But that is based on a lot of speculation. It would be nice to know why such a bizarre (IMHO) requirement was formulated. - tye	[reply]
Re^3: A class that cannot be subclassed. by chromatic (Archbishop) on Feb 28, 2008 at 08:01 UTC
Our coding standards say to prefer composition over subclassing. You have coding standards, so do you have code reviews or some sort of collective code ownership?	[reply]
Re^3: A class that cannot be subclassed. by Anonymous Monk on Feb 28, 2008 at 16:06 UTC
"Our coding standards say to prefer composition over subclassing." That's fine. But do it with documentation, not code.	[reply]