ICFP

Tagless interpreters for well-typed terms in some object language are a standard example of the power and benefit of precise indexing in types, whether with dependent types, or generalized algebraic datatypes. The key is to reflect object language types ...

The zipper type provides the ability to efficiently edit tree-shaped data in a purely functional setting by providing constant time edits at a focal point in an immutable structure. It is used in a number of applications and is widely applicable for ...

We present a framework for constructing functional data structures that can be stored on disk. The data structures reside in a heap saved in a binary file. Operations read and write only the parts of the data structure that are actually needed. The ...

Tools for computer languages need position information: compilers for providing better error messages, structure editors for mapping between structural and textual views, and debuggers for navigating through a term, for instance. Manually adding ...

This paper demonstrates how relational algebraic programming based on efficient symbolic representations of multisets and operations on them can be applied to the query sublanguage of SQL in a type-safe fashion. In essence, it provides a library for ...

Polytypic programming is very useful in functional languages to capture generic functionality, but is of little help to programmers in object-oriented languages. We have developed a form of polytypic programming, which is more object-oriented friendly, ...

Static typing in functional programming languages such as Clean, Haskell, and ML is highly beneficial: it prevents erroneous behaviour at run time and provides opportunities for optimisations. However, dynamic typing is just as important as sometimes ...

When are two types the same? In this paper we argue that isomorphism is a more useful notion than equality. We explain a succinct and elegant approach to establishing isomorphisms, with our focus on showing their existence over deriving the witnesses. ...

The fully polynomial-time approximation scheme (FPTAS) is a class of approximation algorithms that is able to deliver an approximate solution within any chosen ratio in polynomial time. By generalising Bird and de Moor's Thinning Theorem to a property ...