Approximate Component Retrieval: An Academic Exercise or a Practical Concern?

When one uses informal methods to retrieve a component that satisses some requirements out of a software reuse library, one cannot distinguish between the retrieved components that do satisfy the requirements and those that merely approximate the requirements (i.e. almost satisfy them). On the other hand, if one uses formal retrieval methods based on precise speciications of components and queries and on formal matching criteria, then one can clearly distinguish between two retrieval methods: exact retrieval, which seeks to identify components that are proved to satisfy the requirements at hand; and approximate retrieval, which is content with components that do not necessarily satisfy but approximate the requirements at hand. In this paper we advocate the need to make the distinction between these two families of methods, and introduce a possible approach thereto. need for scientiically based methods.