Towards a meaning of LIFE

Abstract

LIFE (Logic, Inheritance, Functions, Equations) is an experimental programming language proposing to integrate three orthogonal programming paradigms proven useful for symbolic computation. From the programmer's standpoint, it may be perceived as a language taking after logic programming, functional programming, and object-oriented programming. ¿From a formal perspective, it may be seen as an instance (or rather, a composition of three instances) of a Constraint Logic Programming scheme due to Hvhfeld and Smolka refining that of Jaffar and Lassez. We start with an informal overview demonstrating LIFE as a programming language, illustrating how its primitives offer rather unusual, and perhaps (pleasantly) startling, conveniences. The second part is a formal account of LIFE's object unification seen as constraint-solving over specific domains. We build on work by Smolka and Rounds to develop type-theoretic, logical, and algebraic renditions of a calculus of order-sorted feature approximations.