Special Issue on State-of-the-Art Applications of Pure Functional Programming Languages

Abstract

Can functional programs be used to build real applications?The mere fact that this question is being asked is encouraging.Functional programming is all too often perceived as an exotic, mostly theoretical activity that has no bearing on reality.1994 saw two events specifically devoted to answering this question.The first was the Dagstuhl workshop on 'Functional programming in the real world', and the second the creation of this special issue.During the Dagstuhl workshop some 30 applications were presented.The call for papers for this special issue attracted 21 submissions.The sheer number of people working on applications indicates that solving real problems using functional languages is now becoming a serious proposition.The contributions in this issue address several diverse application areas: nuclear physics, databases query processing, parallel vision, building a spread sheet, solid modelling and molecular biology.Several other areas such as operational research and engineering design were represented in the papers that could not be included in this issue.A number of papers were also submitted targeting typical computer science applications, such as building parsers, programming environments, and executable specifications.The six papers that make up this issue have been selected purely on the basis of the formal refereeing process.Three of the papers describe prototypes of real systems.These are the database query processing, parallel vision and molecular biology systems.The production systems, which have been developed on the basis of these prototypes are used 'in anger'.The production systems have been implemented respectively as a shell script, a parallel Occam 2 program and as a C++ program.The prototypes are either incomplete, or too slow or space hungry to be used as a real application.The other three papers describe kernel applications, that were built to gain understanding of the problem domain.These are the nuclear physics, spreadsheet and solid modelling programs.These kernel applications are not used as real applications because they are not sufficiently complete to do the job properly.