A proposal for Groovy 2.0: Mixins

Hi all,
  I'm a aficionado of Groovy, so I want Groovy good enough to beat Ruby.
  When I learnt Groovy, I found nothing corresponding to Mixins in Ruby
which is very powerful for programmer to improve productivity. 
  If Groovy wants to have something like Mixins, it can leverage AspectJ.

"Inheritance and Mixins

Some object-oriented languages (such as C++) support multiple
inheritance, where a class can have more than one immediate parent,
inheriting functionality from each. Although powerful, this technique
can be dangerous, as the inheritance hierarchy can become
ambiguous.
Other languages, such as Java and C#, support single inheritance.
Here, a class can have only one immediate parent. Although cleaner
(and easier to implement), single inheritance also has drawbacks—in
the real world objects often inherit attributes from multiple sources (a
ball is both a bouncing thing and a spherical thing, for example).
Ruby offers an interesting and powerful compromise, giving you
the simplicity of single inheritance and the power of multiple inheritance.
A Ruby class has only one direct parent, so Ruby is a singleinheritance
language. However, Ruby classes can include the functionality
of any number of mixins (a mixin is like a partial class definition).
This provides a controlled multiple-inheritance-like capability
with none of the drawbacks. We’ll explore mixins more beginning on
page"   cited from "Programming Ruby"

Best regards,
Daniel.Sun