Beta is no longer being actively maintained.
"BETA has powerful abstraction mechanisms that provides excellent support for design and implementation, including data definition for persistent data. The powerful abstraction mechanisms greatly enhances reusability of designs and implementations.
The abstraction mechanisms include: class, procedure, function, coroutine, process, exception, and many more, all unified to the ultimate abstraction mechanism: the pattern. In addition to the pattern, BETA has subpattern, virtual pattern and pattern variable. This unification of abstraction mechanisms gives a uniform treatment of abstraction mechanisms and a number of new abstraction mechanisms. Most object-oriented languages have classes, subclasses and virtual procedures and some have procedure variables. Since a pattern is a generalization of abstraction mechanisms like class, procedure, function, etc., the notions of subpattern, virtual pattern and pattern variable also apply to these abstraction mechanisms."
Last modified 06 April 2022