This report introduces the programming system PISA intendei for the
interactive production of application software. The heart of the
programming system is a new programming language, also called PISA. An
interactive environment for this language permits the creation, test,
maintenance, and usage of PISA programs in a real-time dialogue fashion.
Both the programming language and its interactive environment are
described without any reference to a specific implementation. Together,
they form a well defined programming system whose components interact
harmoniously. The programming system PISA is dedicated to application
software production. This implies that production of system software and
online-control programs is not a goal of PISA. Furthermore, it means
that PISA must meet several requirements as they arise from commercial
application software production, the most stringent ones being economy,
availability, and compatibility: In the long term the overall cost of
software production and usage with such a programming system must be
less than with conventional means, the programming system must be
available or implementable on a wide range of computer systems currently
used, and existing data must be accessible in its actual physical
representation. The definition of PISA is given in a heavily annotated
form in this report: Examples for the use of single componer.ts as well
as for the entire system are presented, most of the lan uage constructs
and system facilities are commented on briefly, and the implications of
the programming system's design on implementability and portability
issues are discussed.