On the basis for ELF: an extensible language facility

There are two basic premises which underlie the development of ELF. The first of these is that there exists a need for a wide variety of programming languages; indeed, our progress in the understanding and application of computers will demand an ever widening variety of languages. There are, in fact, "scientific" problems, "data processing" problems, "information retrieval" problems, "symbol manipulation" problems, "text handling" problems, and so on. From the point of view of a computer user who is working in one or more of these areas there are certain units of data with which he would like to transact and there are certain unit operations which he would like to perform on these data. The user will be able to make effective use of a computer only when the language facilities provided allow him to work toward a desired result in terms of data and operations which he chooses as being a natural representation of his conception of the problem solution. That is, it is not enough to have a language facility which is formally sufficient to allow the user to solve his problem; indeed, most available programming languages are, to within certain size limitations, universal languages. Rather, the facility must be natural for him to use in the solution of his particular problem.