The persistent store as an enabling technology for integrated project support environments

The software engineering community has recognised the need for integrated project support environments (IPSEs) for some time. With such a system the user is provided with an integrated set of software tools with which to operate. Given this set of integrated software tools rather than a set of ad hoc tools the cost of software and project support throughout its life cycle is reduced. The technique of integration as a method of cost saving, applies to all levels in the hierarchy of problem solving, both hardware and software. This paper discusses one such level, that in which the IPSE is implemented and in particular the use of a persistent store as an enabling technology for IPSEs. The facilities of the language PS-algol necessary to support an IPSE are illustrated by example and it is demonstrated how an IPSE's base may be provided by a persistent store that supports first class procedures as data objects. The need for a type secure object system which allows static and dynamic binding is demonstrated and finally the secure transactional base of PS-algol is shown to be a necessary and sufficient condition to provide secure version control and concurrent access to both programs and data.