Development of an MSC language and compiler, volume 1

Higher order programming language and compiler for advanced computer software system to be used with manned space flights between 1972 and 198

Studies in the design and implementation of programming languages for symbol manipulation

Compared with the development of computing hardware, the development of programming languages has followed a different course. Hardware innovations such as the use of transistors and integrated circuitry have resulted in machines with very substantially improved capabilities, making older machines and even comparatively modern machines obsolescent. The programming languages currently in most widespread use, however, remain those which were already in use as many as ten years ago, namely HJRTRAN, ALGOL 60, and COBOL. Nevertheless, considerable improvements can be made to these languages. The reasons why no improvements were made appear to be primarily twofold. Firstly, they are regarded as 'standard' languages, which in order to facilitate transferability of programs, has made them virtually immutable. Secondly, they can be employed in almost all programming situations without the need for change. Instead, very many other languages have been designed and implemented with particular objectives in view, but which almost invariably limit their application to a narrow field. Only recently have attempts been made to unify some of the developments under the cloak of a single language ( PL/1 and ALGOL 68 ). Data structures are a particular example of what features have been incorporated. There are still considerable omissions however. For instance, neither language has incorporated list processing or symbol manipulation facilities within its basic framework. The latter seems to be most surprising. With the increased capabilities of modern computers and the consequent broadening of their range of application, techniques involving symbol manipulation are becoming increasingly important. Natural language processing such as the analysis of texts for authorship and mechanical translation, and formal manipulations, such as those involved in mechanical theorem-proving and algebraic formula manipulation are some obvious applications. The last mentioned, that of algebraic manipulation of formulae, is one of the most important applications. Several systems, notably R3RMAC, have been developed for this purpose. With the advent of multi-access computing systems a much greater interaction between man and machine is becoming possible, where the advantages of algebraic manipulation and mathematical assistance packages are felt the greatest. This, further, demonstrates the need for symbol manipulation facilities to be available together with normal arithmetic facilities in a programming language, for not only must the formulae be manipulated but also they must be evaluated in normal arithmetic terns. This combination has not completely satisfactorily been acheived in any languages developed in the past. The present investigation is an attempt to overcome this deficiency. A language called ASTRA has been the result. Before discussing the design and implementation of ASTRA, several existing languages are examined in order to discern the desirable properties of a language for symbol manipulation. It is the belief of the present author that the features of ASTRA described herein represent an advance on previous languages. The methods used in the ASTRA compiler are also described

Data structures for algebraic manipulation

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Memoized zipper-based attribute grammars and their higher order extension

Attribute grammars are a powerfull, well-known formalism to implement and reason about programs which, by design, are conveniently modular. In this work we focus on a state of the art zipper-based embedding of classic attribute grammars and higher-order attribute grammars. We improve their execution performance through controlling attribute (re)evaluation by means of memoization techniques. We present the results of our optimizations by comparing their impact in various implementations of different, well-studied, attribute grammars and their Higher-Order extensions. (C) 2018 Elsevier B.V. All rights reserved.- (undefined

The pragmatic formalization of computing systems relative to a given high-level language

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Syntax Directed Analysis and The Compiler Compiler

The Compiler Compiler is the procedure to define an input and an output language as formally as possible, to describe the translation algorithm of a compiler simple and clear, and to generate compilers in a short time easily by means of a computer. As one method, we have constructed the Compiler Oriented Language COL suitable to describe compilers. The compiler described in COL parses an input string in the manner of the Syntax directed analysis, interprets the resulting syntactic structure and produces the output string. In this paper, we discuss two methods of the Syntax directed analysis, Top-down analysis and Bottom-up analysis, and the Syntax Statement of COL in which the parsing procedure of a compiler is described. As a result, it may be said that the resulting compiler described in COL can accept ALGOL programs and produce the object programs in symbolic language or in machine language, and that the parsing time is about 50 percent of the whole compiling time on the average

The Design and Implementation of a Prototype Geographic Information System Using a Novel Architecture Based on PS-Algol

This thesis is concerned with the design and implementation of a novel architecture for a geographic information system based on the use of a new database language called PS-algol, in conjunction with a hybrid database structure. The main aspects discussed within the context of this thesis are:- i) the definition of a database; ii) the components and functions of a database management system; iii) the features of PS-algol; iv) the new system architecture; v) the use of operational management system; vi) data entry as carried out by the system; vii) the facility for the cartographic representation of features; viii) data retrieval and its potential use; and ix) the generation of hard-copy output The thesis also includes a review of existing geographical information systems against which the novelty of the new approach can be judged