Teaching LP: A Perspective Gopal Gupta Department of Computer Science University of Texas at Dallas

Motivation LP: an important paradigm LP: an important paradigm LP: the grand unifying theory of CS LP: the grand unifying theory of CS LP: leads to better understanding of CS LP: leads to better understanding of CS Hence, teaching LP of utmost importance Hence, teaching LP of utmost importance Background: Taught LP courses for 12 years (both graduate/undergraduate) Background: Taught LP courses for 12 years (both graduate/undergraduate) Involved in a project on teaching programming to 1st year students via Prolog (panels in ICLP’92 &’93). Involved in a project on teaching programming to 1st year students via Prolog (panels in ICLP’92 &’93).

Pedagogical Objectives Understand main ideas of LP Understand main ideas of LP Develop an appreciation for the power and uniqueness of LP Develop an appreciation for the power and uniqueness of LP How LP relates to various areas of CS (databases, s/w engg., AI,..) How LP relates to various areas of CS (databases, s/w engg., AI,..) Develop an appreciation for LP’s relation to Constraint Prog/Op. Res. Develop an appreciation for LP’s relation to Constraint Prog/Op. Res. Appreciate LP’s role in reducing the complexity of programming Appreciate LP’s role in reducing the complexity of programming

Teaching of LP in US LP as a paradigm is well recognized in US. LP as a paradigm is well recognized in US. Most US Univ. cover it in a 4 th yr Prog. Lang. course (taught as one of the four paradigms but in a very cursory fashion). Most US Univ. cover it in a 4 th yr Prog. Lang. course (taught as one of the four paradigms but in a very cursory fashion). Many Universities have a dedicated graduate level course in LP. Many Universities have a dedicated graduate level course in LP. At UT Dallas: 120 UG students are exposed to LP every year; about 40 grad students take the dedicated course. At UT Dallas: 120 UG students are exposed to LP every year; about 40 grad students take the dedicated course.

Curriculum at UT Dallas Course Goal: Get main ideas of LP across: Course Goal: Get main ideas of LP across: The basis of LP in theorem proving; computation is deduction The basis of LP in theorem proving; computation is deduction Basic understanding of Prolog’s execution model: unification, search w/ backtracking Basic understanding of Prolog’s execution model: unification, search w/ backtracking Programming with recursion Programming with recursion Relational nature of Prolog programs: invertibility of predicates Relational nature of Prolog programs: invertibility of predicates Applications; Generalization to Constraints Applications; Generalization to Constraints

Ideal Curriculum As part of a Prog. Lang. class: As part of a Prog. Lang. class: - Database programming (datalog) - Database programming (datalog) - Backtracking search - Backtracking search - Recursion/List Proc. - Recursion/List Proc. As a complete course on LP As a complete course on LP - All topics in previous slides - All topics in previous slides

Personal Remarks Need to motivate people to study LP Need to motivate people to study LP Lack of awareness of LP’s power; wrongly perceived as a failed language Lack of awareness of LP’s power; wrongly perceived as a failed language However, once such people take an LP class, they appreciate its power However, once such people take an LP class, they appreciate its power Most students are motivated by “cool” applications; we need to advertise cool applications of LP more. Most students are motivated by “cool” applications; we need to advertise cool applications of LP more. At UTD, application of LP in solving some local problems is a single contributing factor in attracting students to LP classes in large numbers. At UTD, application of LP in solving some local problems is a single contributing factor in attracting students to LP classes in large numbers.