Parker, J.R.2008-05-082008-05-081984-02-01http://hdl.handle.net/1880/46411Data abstraction and type extension are reviewed, and applications to software development are discussed. Methods for assisting PASCAL programmers in constructing and using extended types are developed, and some examples are presented. The Ada language is used as a basis for comparison.EngComputer Scienceunknown1984-144-210.11575/PRISM/30950