Two years after its original inception, and two months after its launch in the US (CI No 907), the Symbolics-developed programming language and software development environment, Joshua, has arrived in the UK. The Cambridge, Massachusetts company claims that by closing the so-called loop between development and delivery, the product transcends, and offers a cost-effective solution to, the limitations of existing toolkits, and places it firmly in the next generation of expert system building products. Up to this point, so the argument goes, expert system toolkits have fallen into one of two categories: large, powerful workstation-based products which, while ideal for development purposes, tend to fall down, performance-wise on application delivery, or smaller, cheaper but far more limited stand-alone packages, designed to run on MS-DOS micros. The key to Joshua’s proclaimed success is flexibility: essentially, its full Lisp capabilities enable integration with – and interfacing to – a wide range of existing software products and systems, significantly expanding the range of external information sources available to the developer, and enhancing the role the product can play within a company’s data-processing department. Meanwhile performance is ensured – via Genera, the Symbolics operating environment – through a range of metering and performance tools, which identify bottlenecks and trace rule firing and queueing. Other performance features include fully compiled backward and forward chaining, the storing of facts and rules in application-specific formats, and an integrated truth maintenance system. Joshua is available on the current range of Symbolics workstations for around UKP30,000, or on Ivory boards which are licensed at UKP12,495. In the UK, the London end of accountancy and management consultancy firm Coopers & Lybrand has already chosen the product for use in the development of a multi national corporate tax planner: Symbolics anticipates a 60% take up rate from existing customers, and currently has signal interpretation, manufacturing control and space applications under development.
