Goal: not to be restrictet to one DSL while not loosing the development tools.
Host and context specific language
polyglot = Mehrsprachig
Goal: Avoid having to spread contextdependent behavior throughout a program
Layers for partial class and methods
each layer has a name
dynamically scoped layer activation obeys a stack-like discipline
Goal: Meta-level functionality should be implemented separately from base-level functionality, using objects known as mirrors
Design principles for meta-level facilities in object oriented programming languages:
Benefit: Dynamic Interface Adaptatio, Dynamic Message Visibility and Dynamic Decision Learning:
Goal: methodological abstraction
"If the advancement of the general art of programming requires the continuing invention and elaboration of paradigms, advancement of the art of the individual programmer requires that he expand his repertory of paradigms."