Semantics and Types in Functional Logic Programming -- Polytypic Programming With Ease -- Type Inference for Overloading without Restrictions, Declarations or Annotations -- Partial Evaluation and Non-interference for Object Calculi -- Lazy Lexing is Fast -- A Functional-Logic Perspective of Parsing -- Implementing Encapsulated Search for a Lazy Functional Logic Language -- Comparison of Deforestation Techniques for Functional Programs and for Tree Transducers -- Automatic Verification Based on Abstract Interpretation -- A Transformation System for Lazy Functional Logic Programs -- Termination Analysis of Tabled Logic Programs Using Mode and Type Information -- On Quasi-Reductive and Quasi-Simplifying Deterministic Conditional Rewrite Systems -- An Interval Lattice-Based Constraint Solving Framework for Lattices -- Higher Order Matching for Program Transformation -- Automated Generalisation of Function Definitions -- An Extensional Characterization of Lambda-Lifting and Lambda-Dropping -- Using Types as Approximations for Type Checking Prolog Programs -- Typed Static Analysis: Application to Groundness Analysis of Prolog and ? Prolog -- A Space Efficient Engine for Subsumption-Based Tabled Evaluation of Logic Programs -- The Logical Abstract Machine: A Curry-Howard Isomorphism for Machine Code -- On Reducing the Search Space of Higher-Order Lazy Narrowing -- Typed Higher-Order Narrowing without Higher-Order Strategies -- A Semantics for Program Analysis in Narrowing-Based Functional Logic Languages.

This volume contains the papers presented at the 4th Fuji International S- posium on Functional and Logic Programming (FLOPS’99) held in Tsukuba, Japan, November 11–13, 1999, and hosted by the Electrotechnical Laboratory (ETL). FLOPS is a forum for presenting and discussing all issues concerning functional programming, logic programming, and their integration. The sym- sium takes place about every 1.5 years in Japan. Previous FLOPS meetings were held in Fuji Susuno (1995), Shonan Village (1996), and Kyoto (1998). 1 There were 51 submissions from Austria ( ),Belgium (2),Brazil(3),China 3 3 1 7 (1), Denmark (2), France (3 ), Germany (8), Ireland (1), Israel ( ), Italy (1 ), 4 3 12 1 Japan (9 ), Korea (1), Morocco (1), The Netherlands (1), New Zealand (1), 3 1 1 3 5 Portugal ( ), Singapore ( ), Slovakia (1), Spain (4 ), Sweden (1), UK (4 ), 2 3 4 6 1 and USA (2 ), of which the program committee selected 21 for presentation. In 4 addition, this volume contains full papers by the two invited speakers, Atsushi Ohori and Mario Rodr´?guez-Artalejo.