A Case study on prototyping with specifications and multiple implementations

This paper presents through an example a software process model addressed to support the existence of multiple implementations when programming with abstract data types. We combine an equational style for specifying types and an imperative one for implementing them. Implementations may be selected by means of ad hoc language constructs in the appropriate contexts; another language construct, the abstraction function, allows implicit switching between implementations during execution and it also allows prototyping of incomplete programs. So, the resulting software process model permits the user to reach the final program as a sequence of intermediate executable prototypes