Prolog (Computer program language)

Gaining the ability to think logically and to understand
strategies of problem solving is a desired goal of
education. This goal is often expressed as learning to
reason. The programming languages currently being
taught feature a systematic breaking down of a problem
into manageable parts instead of stressing an overview
of the entire problem and all its possible implications
in its environment. PROLOG, a computer language which
allows programming in logic, is a descriptive language.
The goals of including PROLOG in the repertoire of a
student's skills are to build a familiarity with a
logical system to approach open-ended questions and
multistep problems and thereby achieve an enhancement of
reasoning abilities. The text and exercises developed
were used to teach reasoning in PROLOG to three groups
of university level students.

G-LOG is a PROLOG semi-compiler written in the C
programming language. G-LOG was designed to be a
transportable, easily extensible non-procedural language
which provides easy access to routines written in other
programming languages. A primary use of G-LOG will be
for the construction of a non-procedural executive for
an expert system which calls existing routines to
execute procedural functions. This versatility should
enable industry investments in complex programs to be
updated into a customized expert system. The history
and philosophy of PROLOG is sketched first, then the
syntax required by G-LOG is presented. The
implementation of G-LOG is discussed in detail. Novel
aspects of G-LOG include semi-compilation of variables
and user-written system primitives. Guidelines for the
application programmer are given.