916 papers · page 28 of 46
You are holding a necklace in your hands, composed of no fewer than thirteen exquisite pearls. The pearls are from all over the world, selected for the finest quality, smoothness and lustre. For your viewing pleasure, the necklace emphasizes variety, stringing pearls of wildly di…
This issue of the Journal of Functional Programming marks a point of transition. Our long-time Chief Editors, Simon Peyton Jones and Philip Wadler, are stepping down. Most of us are aware of the amazing research contributions that Simon and Phil have made to functional programmin…
Haskell today provides good support not only for a functional programming style, but also for an imperative one. Elements of imperative programming are needed in applications such as web servers, or to provide efficient implementations of well-known algorithms, such as many graph…
This paper describes a simple but flexible family of Haskell programs for drawing pictures of fractals such as Mandelbrot and Julia sets. Its main goal is to showcase the elegance of a compositional approach to program construction, and the benefits of a clean separation between …
The tedium of writing pickling and unpickling functions by hand is relieved using a combinator library similar in spirit to the well-known parser combinators. Picklers for primitive types are combined to support tupling, alternation, recursion, and structure sharing. Code is pres…
Proof systems for expressive type theories provide a foundation for the verification and synthesis of programs. But despite their successful application to numerous programming problems there remains an issue with scalability. Are proof environments capable of reasoning about lar…
This paper implements a simple and elegant version of bottom-up Kilbury chart parsing (Kilbury, 1985; Wirén, 1992). This is one of the many chart parsing variants, which are all based on the data structure of charts. The chart parsing process uses inference rules to add new edges…
This book describes theoretical results about AnsProlog * that have been obtained over the past decade.AnsProlog * or Prolog with Answer Sets 1 is a variation of the Prolog programming language, and extends the language by allowing clauses of the form:in the program.The L i 's ar…
We give transparent proofs of the PTIME-completeness of two decision problems for terms in the λ-calculus. The first is a reproof of the theorem that type inference for the simply-typed λ-calculus is PTIME-complete. Our proof is interesting because it uses no more than the standa…
This work presents simple decision procedures for the propositional calculus and for a simple predicate calculus. These decision procedures are based upon enumeration of the possible values of the variables in an expression. Yet, by taking advantage of the sequential semantics of…
Pattern matching has proved an extremely powerful and durable notion in functional programming. This paper contributes a new programming notation for type theory which elaborates the notion in various ways. First, as is by now quite well-known in the type theory community, defini…
Haskell code is developed for two ways to list the strings of the language defined by a regular expression: directly by set operations and indirectly by converting to and simulating an equivalent automaton. The exercise illustrates techniques for dealing with infinite ordered dom…
We describe the FC++ library, a rich library supporting functional programming in C++. Prior approaches to encoding higher order functions in C++ have suffered with respect to polymorphic functions from either lack of expressiveness or high complexity. In contrast, FC++ offers fu…
The Sieve of Eratosthenes is an efficient algorithm for computing the successive primes. Rendered informally, it is as follows: 1. Write down the successive “plurals”: 2, 3, 4, … 2. Repeat: (a) Take the first number that is not circled or crossed out. (b) Circle it. (c) Cross out…
Using Haskell as a digital circuit description language, we transform a ripple carry adder that requires $O(n)$ time to add two $n$ -bit words into a parallel carry lookahead adder that requires $O(\log n)$ time. The ripple carry adder uses a scan function to calculate carry bits…
Grammatical Framework (GF) is a special-purpose functional language for defining grammars. It uses a Logical Framework (LF) for a description of abstract syntax, and adds to this a notation for defining concrete syntax. GF grammars themselves are purely declarative, but can be us…
This book describes theoretical results about AnsProlog * that have been obtained over the past decade.AnsProlog * or Prolog with Answer Sets 1 is a variation of the Prolog programming language, and extends the language by allowing clauses of the form:in the program.The L i 's ar…
This book describes theoretical results about AnsProlog * that have been obtained over the past decade.AnsProlog * or Prolog with Answer Sets 1 is a variation of the Prolog programming language, and extends the language by allowing clauses of the form:in the program.The L i 's ar…
In this paper, we describe two techniques for the efficient, modularized implementation of a large class of algorithms. We illustrate these techniques using several examples, including efficient generic unification algorithms that use reference cells to encode substitutions, and …