I Language Features

Chapter 1 Introduction

Curry is a universal programming language aiming at the amalgamation of the most important declarative programming paradigms, namely functional programming and logic programming. Curry combines in a seamless way features from functional programming (nested expressions, lazy evaluation, higher-order functions), logic programming (logical variables, partial data structures, built-in search), and concurrent programming (concurrent evaluation of constraints with synchronization on logical variables). Moreover, Curry provides additional features in comparison to the pure languages (compared to functional programming: search, computing with partial information; compared to logic programming: more efficient evaluation due to the deterministic evaluation of functions). Moreover, it also amalgamates the most important operational principles developed in the area of integrated functional logic languages: “residuation” and “narrowing” (see [13, 19] for surveys on functional logic programming).

The development of Curry is an international initiative intended to provide a common platform for the research, teaching11Actually, Curry has been successfully applied to teach functional and logic programming techniques in a single course without switching between different programming languages. More details about this aspect can be found in [14]. and application of integrated functional logic languages.

This document is intended to provide a tutorial introduction into the features of Curry and their use in application programming. It is not a formal definition of Curry which can be found in [11].