Description
A COLA is designed to be the simplest possible language which can be described in itself, so that the implementation exactly describes itself. In order to do this the structure of the environment is separated from the semantics of the computation performed.
The object system describes the structure of a prototype-based Object Oriented environment. This is implemented in terms of objects and message passing, which is in fact the same system it is describing. This allows modification of the system by using the same object oriented knowledge used to write any other application.
This object system is turned into a useful programming language by complementing it with a functional language describing what each object's methods do. The methods called from the object language are closures running a functional programming language.
Combined together, these two parts form a complete prototype-based Object Oriented programming language which is entirely self-hosting.
Read more about this topic: COLA (software Architecture)
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