We describe the implementation of first-class polymorphic delimited continuations in the programming language Scala. We use Scala's pluggable typing architecture to implement a simple type and effect system, which discriminates expressions with control ...

Continuation-based Web servers provide distinct advantages over traditional Web application development: expressive power and modularity. This power leads to fewer errors and more interesting applications. Furthermore, these Web servers are more than ...

In Concurrent ML, synchronization abstractions can be defined and passed as values, much like functions in ML. This mechanism admits a powerful, modular style of concurrent programming, called higher-order concurrent programming. Unfortunately, it is ...

Attribute Grammars (AGs), a general-purpose formalism for describing recursive computations over data types, avoid the trade-off which arises when building software incrementally: should it be easy to add new data types and data type alternatives or to ...

I describe the initial attempt of experienced business software developers with minimal functional programming background to write a non-trivial, business-critical application entirely in Haskell. Some parts of the application domain are well suited to ...

Memoization is a well-known optimization technique used to eliminate redundant calls for pure functions. If a call to a function f with argument v yields result r, a subsequent call to f with v can be immediately reduced to r without the need to re-...

Type abstraction and intensional type analysis are features seemingly at odds-type abstraction is intended to guarantee parametricity and representation independence, while type analysis is inherently non-parametric. Recently, however, several ...

This pearl aims to demonstrate the ideas of wholemeal and projective programming using the Towers of Hanoi puzzle as a running example. The puzzle has its own beauty, which we hope to expose along the way.

Alan Perlis, inverting OscarWilde's famous quip about cynics, once suggested, decades ago, that a Lisp programmer is one who knows the value of everything and the cost of nothing. Now that the conference on Lisp and Functional Programming has become ICFP,...

Many datatype-generic functions need access to the recursive positions in the structure of the datatype, and therefore adopt a fixed point view on datatypes. Examples include variants of fold that traverse the data following the recursive structure, or ...

We describe in this paper our implementation of the Xenstored service which is part of the Xen architecture. Xenstored maintains a hierarchical and transactional database, used for storing and managing configuration values.

We demonstrate in this paper ...

Free theorems are a charm, allowing the derivation of useful statements about programs from their (polymorphic) types alone. We show how to reap such theorems not only from polymorphism over ordinary types, but also from polymorphism over type ...

Arrows are a popular form of abstract computation. Being more general than monads, they are more broadly applicable, and in particular are a good abstraction for signal processing and dataflow computations. Most notably, arrows form the basis for a ...