Algebraic Logic Functional language
(ALF) A language by Rudolf Opalla <email@example.com> which combines functional programming and logic programming techniques.
ALF is based on Horn clause logic with equality which consists of predicates and Horn clauses for logic programming, and functions and equations for functional programming. Any functional expression can be used in a goal literal and arbitrary predicates can occur in conditions of equations. ALF uses narrowing and rewriting.
ALF includes a compiler to Warren Abstract Machine code and run-time support.
["The Implementation of the Functional-Logic Language ALF", M. Hanus and A. Schwab].