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This article presents several research papers related to computing machinery and computer programs. Designing a system for the analytic processing of mathematical functions around a central syntax processor and permitting the user to work within the context of mathematical syntax leads to a flexible system with a broad range of capabilities. One advantage of the approach mentioned in "A Syntax-Directed Approach to Automated Aids for Symbolic Math," by L. Clapp, is that the basic system can be developed without many a prior restrictions on the nature of the mathematical entities to be processed. Once the basic structure has been developed, the user is free to define and operate within his own system of mathematics by modifying or extending the syntax definitions. In the paper "Programming Languages, Logic and Cooperative Games," by L. Hodes, an application of computers is presented which is not restricted to a single problem area but is perhaps not general purpose enough to be considered programming language, even a problem-oriented one.

This paper modifies an earlier algorithm for converting decision tables into flowcharts which minimize subsequent execution time when compiled into a computer program. The algorithms considered in this paper perform limited search and, accordingly, do not necessarily result in globally optimal solutions. However, the greater search effort needed to obtain a globally optimal solution for complex decision tables is usually not justified by sufficient savings in execution time. There is an analogy between the problem of converting decision tables into efficient flowcharts and the well-understood problem in information theory of noiseless coding. The results of the noiseless coding literature are used to explore the limitations of algorithms used to solve the decision table problem. The analogy between the two problems is also used to develop improvements to the information algorithm in extending the depth of search under certain conditions and in proposing additional conditions to be added to the decision table. Finally, the information algorithm is compared with an algorithm proposed in a recent paper by Verhelst. [ABSTRACT FROM AUTHOR]

This paper discusses both the history and future of programming languages (= higher level languages). Some of the difficulties in writing such a history are indicated. A key part of the paper is a tree showing the chronological development of languages and their interrelationships, Reasons for the proliferation of languages are given. The major languages are listed with the reasons for their importance. A section on chronology indicates the happenings of the significant previous time periods and the major topics of 1972. [ABSTRACT FROM AUTHOR]

User-written programs on the Dartmouth Time-Sharing System can communicate with many remote terminals simultaneously and can control the interactions between these terminals. Such programs can be written using standard input and output instructions in any language available on the system. This paper describes how this multiple-terminal facility was implemented without requiring any changes in the system executive or in any of the system's compilers or interpreters. [ABSTRACT FROM AUTHOR]

Programming systems which permit arbitrary linked list structures enable the user to create complicated structures without sufficient protection. Deletions can result in unreachable data elements, and there is no guarantee that additions will be performed properly. To remedy this situation, this paper proposes a Data Structure Description and Manipulation Language which provides for the creation of a restricted class of data structures but ensures the correctness of the program. This is accomplished by an explicit structure declaration facility, a restriction on the permissible operations, and execution-time checks. [ABSTRACT FROM AUTHOR]

An increasing amount of software is being implemented in a portable form. A popular way of accomplishing this is to encode the software in a specially designed machine-independent language and then to map this language, often using a macro processor, into the assembly language of each desired object machines The design of the machine-independent language is the key factor in this operation. This paper discusses the relative merits of pitching this language at a high level or a low level, and presents sonic comparative results. [ABSTRACT FROM AUTHOR]

Most current programming languages treat computation over different classes of objects (e.g. numbers, strings, labels and functions). For correct compilation and execution, the following question then arises: is a program properly constructed so that its operations and operands are compatible? The activity of answering this question is usually called type checking. This paper attempts to isolate the notion of type checking and presents a partial solution to the type checking problem based on the notions of abstraction and application of functions. In particular, a program is mapped into an expression within a decideable subset of the λ-calculus, which characterizes the type relations within the program and eliminates all other information The determination of the type-wise correctness or incorrectness of the program is resolved by reducing its corresponding λ-calculus expression to one of two normal forms, the constant "correct" for a type-wise correct program or the constant "error." An application to type checking in Algol 60 is made, and the attendant problems faced for any notion of type checking are discussed. [ABSTRACT FROM AUTHOR]

List processing systems should be designed to facilitate production of large programs to manipulate large complex symbolic data stores. This paper presents an overview of a number of system features which the author feels are important to improve the productivity of programmers working in such domains. A systems view is taken, rather than focusing just on language features, since algorithms must be not only coded in a language form, but debugged, modified, made efficient, and run on data Because of this general framework, the requirements specified are applicable to the design of advanced programming systems for a wide range of applications Three aspects of programming systems are highlighted good interactive facilities, programmable control structures, and sophisticated data communication mechanisms Interactive features are described to facilitate program composition, entry, testing, debugging, editing, optimization, and packaging. Implementation of a generalized environment structure model specified would allow programming of various control regimes including multi processes, coroutines and backtracking. Alternative methods of procedure invocation required include invocation by pattern and by monitoring condition. The need for extended data forms, storage management, and extensibility are stressed, as is the duality of data retrieval and function evaluation. Syntax directed input and output of data would facilitate use of complex data stores. [ABSTRACT FROM AUTHOR]

This paper presents an approach to writing specifications for parts of software systems. The main goal is to provide specifications sufficiently precise and complete that other pieces of software can be written to interact with the piece specified without additional information. The secondary goal is to include in the specification no more information than necessary to meet the first goal. The technique is illustrated by means of a variety of examples from a tutorial system. [ABSTRACT FROM AUTHOR]

A sequential pattern recognition (SPR) procedure does not test all the features of a pattern at once. Instead, it selects a feature to be tested. After receiving the result of that test, the procedure either classifies the unknown pattern or selects another feature to be tasted, etc. Medical diagnosis is an example of SPR. In this paper the authors suggest that SPR be viewed as a one-person game played against nature (chance). Virtually all the powerful techniques developed for searching two-person, strictly competitive game trees can easily be incorporated either directly or by analogy into SPR procedures. In particular, one can incorporate the "miniaverage backing-up procedure" and the "gamma procedure," which are the analogues of the minimax backing-up procedure and the alpha-beta procedure," respectively. Some computer simulated experiments in character recognition ore presented. The results indicate that the approach is promising. [ABSTRACT FROM AUTHOR]

Time-shared, multiprogrammed, and overlayed batch systems frequently require segmentation of computer programs into discrete portions. These program portions are transferred between executable and peripheral storage whenever necessary; segmentation of programs in a manner that reduces the frequency of such transfers is the subject of this paper. Segmentation techniques proposed by C. V. Ramamoorthy are subject to limitations that arise when the preferred segment size is not compatible with the physical restrictions imposed by the available computing equipment. A generalization of Ramamoorthy's suggestions is made in order to allow their ape plication when circumstances are other than ideal. [ABSTRACT FROM AUTHOR]

In this paper an attempt is made to explore the logical foundations of computer programming by use of techniques which were first applied in the study of geometry and have later been extended to other branches of mathematics. This involves the elucidation of sets of axioms and rules of inference which con be used in proofs of the properties of computer programs. Examples are given of such axioms and rules, and a formal proof of a simple theorem is displayed. Finally, it is argued that important advantages, both theoretical and practical, may follow from a pursuance of these topics. [ABSTRACT FROM AUTHOR]

For the nonprogrammer, difficulty in using language increases rapidly with the number of nonproblem-oriented conventions. A simple language, even if inelegant, which considers the user's background as part of the problem may be more effective than 'source language containing subtle and more powerful capabilities. The language described in this paper is used to write computer programs which test electronic equipment. Because this testing process contains few complex ideas, there is little need for the elegance and redundancy of a highly syntax-oriented language. A simple and direct language will suffice for the problem. The eventual users of this language are military depot personnel who cannot be expected to have computer programming skill or significant programming training. For this nonprogramming-oriented user, it was essential to create language using familiar engineering statements; programming- oriented conventions would have unnecessarily complicated his task. [ABSTRACT FROM AUTHOR]

When the transition has been mode from off line to online programming, there are a number of changes in the working conditions noted. These changes in the environment make necessary corresponding changes in the processes related to producing and checking out programs. In the main, it is not the programming language itself which must be changed to provide facility for the online user; it is the system surrounding the programming language. In this paper the online environment and its effect on programming ore discussed. [ABSTRACT FROM AUTHOR]

This paper describes a technique designed to ease the use of a data processing system by a person, in particular, a scientist, who is intimately and primarily concerned with interpreting the significance of data handled by the system. Since such a person is often unable to spend the time necessary to master a programming language, it is essential that he be aided in composing commands to the computer. In the system described, the user is not required to learn or remember the vocabulary of the language because the vocabulary is displayed before him on "menus' by means of a computer-drive scope. He selects the various vocabulary elements required by pointing with the lightpen. By use of a small unordered set of rewriting rules applied as a result of lightpen selections, the user generates only syntactically correct commands to the system. He does not have to learn or remember the grammar. The program restricts the user severely in the particular language he can use, but the method for communicating with the program makes these restrictions seem quite natural and unconstraining. The program has been used successfully for over ten months. [ABSTRACT FROM AUTHOR]

The article presents information on the 1970 Fall Joint Computer Conference that will be held in Houston, Texas, on November 17-19. The conference will have a truly Texas-sized setting, the Astrohall, the world's largest convention and exhibit structure. The technical program may also appear to be Texas-sized in view of its size and diversity. However, it is not so much the program that has grown as the computer industry. The program has therefore been expanded to reflect new developments in computer usage and technology while maintaining its emphasis on various subjects of continuing importance. One of the chief areas of interest is computer software, its present problems and future promises. Two sessions will be devoted on it. Session 21, chaired by M.A. Melkanoff, University of California at Los Angeles, is devoted to the three principal and self-excluding approaches to long-range programming language development being advocated today. A distinguished panel will present a position paper on each of the three approaches and a fourth position paper on relevant research problems.

The article focuses on a paper indicating the error of algorithmic language ALGOL 60 pointed up by the Algorithm 355 construct in the October 1969 issue of the periodical "Communications of the Automation for Computing Machinery." The procedure statement "p" occurs in the body of this procedure, showing "p" to be a procedure without parameters. As originally submitted, the algorithm contained several procedure statements in which p was replaced by a procedure statement. It is possible that the authors of ALGOL 60 intended to permit this but they did not do so. The author's original form may have been more in the sprit of the ALGOL 60 report but the published form confirms to the syntax of ALGOL 60 as described in the report.