chriseppstein/sass — comment on commit 52c9084c1e1258473d00274fbf210d6c44ae14ad
File: doc-src/SASS_REFERENCE.md line 1475
By chriseppstein:

Ok. I understand. Allowing @extend to apply to mixins was considered but ultimately rejected because mixins don't participate in the cascade. I don't see a need to create a new concept here -- I want to build on the existing concept of the class for this feature. I really do consider these abstract base classes in the object oriented sense. This feature doesnt just apply to a single class definition -- it applies to all rulesets that use the class. E.g the selector `#context .base a` is also silenced if you silence `.base`. This is why I was them to live in and be part I the document selector domain.