5.1. Adherence to the open-closed principle
AO solutions generally require more new components to implement a change. In
comparison the OO implementation require existing components to be modified more
extensively to implement the same change. This behavior is confirmed in the change
propagation metrics whereby much more extensive changes (in terms of
added operations and LOC) occur in the OO implementations. Up to 80% fewer
operations and up to 51.54% fewer LOC (note that this LOC is only related to DbC
features such as preconditions) are added in the AO implementations throughout the
scenarios. This indicates that the AO solutions conform more closely to the Open-
Closed principle which states that software should be open for extension, but
closed for modification".
.