Amalgamation of Functional and Logic Programming Languages

摘要

The paper presents an approach to the amalgamation of functional and logic programming concepts. Two sublanguages are provided to separate the functional and logic worlds conceptually. A uniform syntax and the term universe as a common data domain are used. The interaction of both worlds is obtained by means of Horn logic guards which appear as constraints of function equations. The approach is a functional one, because logic evaluations are called from functions, but not vice versa. Its operational semantics comprise eager and lazy evaluation. Thus, infinite data structures can be handled properly. The paper discusses several restrictions to the interface which retain the functional and logic properties respectively. It shows that the resulting language is still functional. A transformation to Prolog as its implementation is discussed, including an outline of optimizations. (Copyright (c) GMD 1989.)