Introducing CLOVER: an Object-Oriented Functional Language
Lee Braine and Chris Clack

Department of Computer Science, University College London,
Gower Street, London WC1E 6BT, UK
L.Braine@cs.ucl.ac.uk C.Clack@cs.ucl.ac.uk

Abstract. The search for a language which combines both functional
and object-oriented features has a long and distinguished history [Can82,
Car84, BK86, BD88, BGW91, MHH91, AP93, CL91, MMH91, Sar93,
CL96]. The aim is to integrate the formal methods benefits of functional
programming with the software engineering benefits of both paradigms.
However, to date we know of no language which can claim to be both
purely functional and purely object-oriented (and retains complete type
safety). We present CLOVER, a new language which is 100% functional
and 99% object-oriented. It is also completely type safe. We explain the
design issues and how CLOVER achieves its aim. We also explain the
``missing'' 1%, discuss its relevance, and illustrate how its loss can be
extenuated through the use of a new visual programming notation.