CONVERT(ID:249/con041)String processing language hybrid of COMIT and LISPString processing language, combined the pattern matching and transformation operations of COMIT with the recursive data structures of Lisp. A language (based on LISP) and routines to handle transformation rules of the type as in COMIT and SNOBOL. (Sammet 1966) Structures: Related languages
References: in [ACM] CACM 9(08) August 1966 view details in [ACM] CACM 9(08) August 1966 view details An unusual and important feature of CONVERT is its use of a dictionary to define variable patterns (and formats -- or skeletons as the authors call them) to use in the matching (and reconstruction) process, in addition to the usual repertoire of standard elementary patterns that can be coneatenated to specify compound structures. A variable in a pattern (any symbol not in the standard repertoire) is specified in a dictionary by two items -- a function which specifies the conditions under which this variable matches part of the structure under consideration; and a slot, in which this function can store information about the part of the struc ture it matched. A unique feature of these functions is th they can change the function associated with a varia name, so that later occurrences of a variable in a patt may have a different meaning than earlier occurrences the same variable. This use of dictionary variables allo the user great flexibility in defining his own language expressing complex context-dependent transformations. The CONVERT language is very powerful and correspo ingly complex. The reader is well advised to study the deceptively simple and beautiful example given at the end of the paper. It expresses in half a page an algorithm differentiating and simplifying algebraic expressions in in form, going through an intermediate prefix form, and of putting the answer again in infix notation. The paper terse, but well written, and contains a number of very interesting ideas. in ACM Computing Reviews 8(01) January-February 1967 view details in ACM Computing Reviews 8(01) January-February 1967 view details in ACM Computing Reviews 8(01) January-February 1967 view details in ACM Computing Reviews 8(01) January-February 1967 view details in ACM Computing Reviews 8(01) January-February 1967 view details in [iEEE] Proceedings of the IEEE 55(8) August 1967 view details in [iEEE] Proceedings of the IEEE 55(8) August 1967 view details in [iEEE] Proceedings of the IEEE 55(8) August 1967 view details in [iEEE] Proceedings of the IEEE 55(8) August 1967 view details in Bobrow, D. G. (ed) "Symbol Manipulation Languages and Techniques", Proceedings of the IFIP Working Conference on Symbol Manipulation Languages. North-Holland Publishing Co., Amsterdam, 1968 view details in Bobrow, E. C. and Bobrow, D. G. (eds). The Programming Language LISP: Its Operations and Applications, Vol. II; Berkeley, MIT Press, Cambridge, Mass. 1969. view details in Computers & Automation 21(6B), 30 Aug 1972 view details The exact number of all the programming languages still in use, and those which are no longer used, is unknown. Zemanek calls the abundance of programming languages and their many dialects a "language Babel". When a new programming language is developed, only its name is known at first and it takes a while before publications about it appear. For some languages, the only relevant literature stays inside the individual companies; some are reported on in papers and magazines; and only a few, such as ALGOL, BASIC, COBOL, FORTRAN, and PL/1, become known to a wider public through various text- and handbooks. The situation surrounding the application of these languages in many computer centers is a similar one. There are differing opinions on the concept "programming languages". What is called a programming language by some may be termed a program, a processor, or a generator by others. Since there are no sharp borderlines in the field of programming languages, works were considered here which deal with machine languages, assemblers, autocoders, syntax and compilers, processors and generators, as well as with general higher programming languages. The bibliography contains some 2,700 titles of books, magazines and essays for around 300 programming languages. However, as shown by the "Overview of Existing Programming Languages", there are more than 300 such languages. The "Overview" lists a total of 676 programming languages, but this is certainly incomplete. One author ' has already announced the "next 700 programming languages"; it is to be hoped the many users may be spared such a great variety for reasons of compatibility. The graphic representations (illustrations 1 & 2) show the development and proportion of the most widely-used programming languages, as measured by the number of publications listed here and by the number of computer manufacturers and software firms who have implemented the language in question. The illustrations show FORTRAN to be in the lead at the present time. PL/1 is advancing rapidly, although PL/1 compilers are not yet seen very often outside of IBM. Some experts believe PL/1 will replace even the widely-used languages such as FORTRAN, COBOL, and ALGOL.4) If this does occur, it will surely take some time - as shown by the chronological diagram (illustration 2) . It would be desirable from the user's point of view to reduce this language confusion down to the most advantageous languages. Those languages still maintained should incorporate the special facets and advantages of the otherwise superfluous languages. Obviously such demands are not in the interests of computer production firms, especially when one considers that a FORTRAN program can be executed on nearly all third-generation computers. The titles in this bibliography are organized alphabetically according to programming language, and within a language chronologically and again alphabetically within a given year. Preceding the first programming language in the alphabet, literature is listed on several languages, as are general papers on programming languages and on the theory of formal languages (AAA). As far as possible, the most of titles are based on autopsy. However, the bibliographical description of sone titles will not satisfy bibliography-documentation demands, since they are based on inaccurate information in various sources. Translation titles whose original titles could not be found through bibliographical research were not included. ' In view of the fact that nany libraries do not have the quoted papers, all magazine essays should have been listed with the volume, the year, issue number and the complete number of pages (e.g. pp. 721-783), so that interlibrary loans could take place with fast reader service. Unfortunately, these data were not always found. It is hoped that this bibliography will help the electronic data processing expert, and those who wish to select the appropriate programming language from the many available, to find a way through the language Babel. We wish to offer special thanks to Mr. Klaus G. Saur and the staff of Verlag Dokumentation for their publishing work. Graz / Austria, May, 1973 in Computers & Automation 21(6B), 30 Aug 1972 view details Extract: CONVERT The specification of a context free grammar in BNF is an example of a set of rewriting rules that are order independent. The CONVERT package (Guzman and Mclntosh, 1966) is an example of the introduction of pattern matching facilities into LISP. in Proceedings of the ACM SIGPLAN symposium on Very high level languages, March 28-29, 1974, Santa Monica, California, United States view details in [SIGPLAN] SIGPLAN Notices 25(07) July 1990 view details |