What is the purpose of using mixin?

Mixins encourage code reuse and can be used to avoid the inheritance ambiguity that multiple inheritance can cause (the “diamond problem”), or to work around lack of support for multiple inheritance in a language. A mixin can also be viewed as an interface with implemented methods.

Mixins are very helpful when we want to share a behavior across multiple classes that don’t share the same class hierarchy, or when it doesn’t make sense to implement such a behavior in a superclass.16 Eyl 2018

“To implement a mixin, create a class that extends Object and declares no constructors . Unless you want your mixin to be usable as a regular class, use the mixin keyword instead of class .”15 Ara 2018