FunZ designs-a bridge between Z specifications and Haskell implementations

FunZ, an intermediate specification language, is part of a complete methodology designed to facilitate the derivation of purely functional programs from Z specifications. FunZ is actually an extension of Haskell, yet the language also retains a Z-like flavor in that it contains notational conventions similar to those of standard Z or several object oriented variants. By combining features from both Z and Haskell, FunZ provides a bridge between Z specifications and Haskell implementations. Although the intermediate language and associated methodology target Haskell, the approach itself is general and can also be applied to other purely functional languages. The paper highlights one facet of the methodology, namely the procedure to derive concrete predicates written in FunZ from their abstract Z counterparts. In addition, by means of an example, the paper gives an overview of the translation process from Z specifications to FunZ designs.