The Open-Closed Principle, in review (2013)

Another modernised statement of the OCP:

https://softwareengineering.stackexchange.com/a/348114

> Derek Elkins: A more abstract and relevant statement of the OCP is: "a component should allow for extension without need of violating its abstraction boundaries". I would go further and say a more modern rendition is: "a component should enforce its abstraction boundaries but allow for extension".