The primary focus of our business is information systems software. This involves computers and communication which have given rise to some of the most controversial issues of our age. On this page we offer our own editorial contribution.

Structured Development

    The ability to adapt quickly to the changing needs of customers is vital to success in the information systems business. The single most important characteristic of an information system is that it is readily changeable in the face of the inevitable changing requirements of its users. The approach utilized in developing computer based solutions is critical to addressing this requirement for adaptability. WISL employs a very structured approach in developing its applications, the results of which are solutions that incorporate a great deal of flexibility and allow for responsive alterations. There is a hierarchy of considerations that contribute to making information systems adaptable.   

    The most basic developmental choice is that of the computing environment(which may be considered as the hardware and operating system employed). Historically major business systems were developed on the proprietary hardware and operating system of a major computer company. Examples were IBM's MVS or DEC's VMS.

    The advent of the personal computer with its fairly monolithic operating environment paralleled the evolution of the "Open Systems" environment for multi-user applications. The various flavors of UNIX, LINUX and Windows NT belong in this grouping. The standards that form the basis of "Open Systems" permit the same application to run on a variety of computing platforms from various vendors. Even if a customer's legacy information systems run on a proprietary environment such as IBM AS/400 facilities are commonplace that make it easy to interface with "Open Systems" based applications. Hence WISL selected "Open Systems" as the computing environment on which to offer its products.

    A data base management system includes facilities for storing and accessing data. There are international standards that must be met to consider a DBMS as "relational". There are many commercial DBMS's that meet these criteria but WISL chose one that has additional features that contribute to the capacity for adaptability. UniVerse incorporates a data element dictionary and handles variable- length fields and variable-occurrence fields and groups in records.

     UniVerse Basic offers similar features as other development languages such as Visual Basic but also provides for integration with other UniVerse processors(e.g. RETRIEVE and PROC). The facilities of WISL's development system, SCADS, are written in UniVerse Basic.

    A development system is a framework to assist programmers to develop applications in a structured manner that will incorporate the standards of the developer. Use of such a system can significantly reduce the time required to develop an application by incorporating standard macros to handle the more mundane aspects of development such as screen formatting and standard user input editing. Even more importantly it results in applications with a standard structure which can significantly reduce the time required by a different person to become familiar with the application in order to make inevitable changes in the future. A detailed description of WISL's development system SCADS may be found in the Technical Notes section of this newsletter.

    The best development system cannot insure effectively programmed applications. There are aspects of every information system application that require the creative abilities of a programmer. During supervision of the development process WISL attempts to insure that a sound structured approach is taken and that certain practices are not employed.

    Most languages(including UniVerse Basic) allow a "GOTO" command. Use of this command results in a program flow that can be very difficult to analyze and can easily result in dangerous infinite loops which can be difficult to diagnose in development or that may only manifest themselves mysteriously months after implementation. WISL discourages use of this command in favor of the employment of subroutines where the control of the program always returns to the point of calling.

    There is a tendency for a programmer to code lists of possible values of a variable directly into the program(e.g. three possible colors, blue, red and yellow). If the application subsequently requires that the color green be added as a possible value then the program must be changed and re-compiled and re-distributed to the customer base. Instead the list of values should be kept in a file(or table) external to the program which may be maintained independently. In many cases the additional value may be added to the table and there may be no requirement to change and re-compile and re-distribute the program.

    These examples illustrate that effective programming techniques can result in significantly lower costs in developing and maintaining applications which translates into lower costs and better responsiveness to problems.