New Programming Languages for Artificial Intelligence Research

New directions in Artifical Intelligence research have led to the need for certain novel features to be embedded in programming languages. This paper gives an overview of the nature of these features, and their implementation in four principal families of AI languages: SAIL; PLANNER/CONNIVER;QLIPS/INTERLISP; and POPLER/POP-2. The programming feature described include: new data types and accessing mechanisms for stored expressions; matching to allow caomparison of data item with a template, and extraction of labeled subexpressions; and deductive mechanisms which allow the programming system to carry out certain activities including modifying the data base and deciding which subroutines to run next using only constraints and guidelines set up by the programmer.