The functional life cycle model and its automation: USE.IT

Recently there has been an accelerated awareness of the urgent need for effective system development tools and techniques. Towards this end attempts have been made to develop standard languages for programming and standard techniques for the front end of the development process. Further, there has even been talk of integrating the various processes within a system life cycle. Our thesis, here, is that although these are steps leading in the right direction, they are simply not enough. What we suggest is needed, rather, is a totally new life cycle model; it is based on pure functional needs. This is in contrast to the ''event'' driven model that has been forced into being based on constraints which are often unnecessary, wasteful, and error prone. The functional model, itself formally defined, not only includes formal techniques for defining the front end, but it also includes techniques which integrate by means of formal methods and automation that front end to the rest of the life cycle of a system. A functional life cycle model has been defined. USE.IT, an implementation of this model, provides for an integrated and automated development process of a system. We discuss, here, the HOS functional model, USE.IT, and the implications of their use.