Generic functional programming with types and relations

A generic functional program is one which is parameterised by datatype. By installing specific choices, for example Iists or trees, different programs are obtained that are, nevertheless, abstractly the same. The purpose of this paper is to explore the possibility of deriving generic programs. Part of the theory of lists that deals with segments is recast as a theory about 'segments' in a wide class of datatypes, and then used to pose and solve a generic version of a well-known problem