PPL(ID:454/ppl001)

Polymorphic Programming Language 

Polymorphic Programming Language.
Initial work at National University of Mexico 1969-71
Development at Harvard U by T A Standish on a DEC System-10 1972. Interactive and extensible, based on APL, but with influences from JOSS and LCC (extension mechanism etc)
Places
Related languages
APL => PPL   Extension of
JOSS => PPL   Influence
LCC => PPL   Influence
References:
  • Standish, T.A. "Some Features of PPL A Polymorphic Programming Language" view details
          in SIGPLAN Notices 4(08) August 1969 view details
  • Standish, Thomas A. "PPL - an extensible language that failed" pp144-145 view details Abstract: PPL, a conversational extensible language, has been running on the DEC PDP-10 for over a year now. Its applications have included: matrix, vector, polynomial, rational and complex arithmetic; formula, list, string, tree and graph manipulation; significant programs in real-time radar air traffic control simulation and parser generation for context-free languages; and a host of useful conversational tasks in population biology, algebra word problems and optimization of programs. Indeed, the parser for another extensible language(ECL) was generated in PPL(using the De Remer algorithm). PPL is now used by over 450 students in Harvard's introductory programming course. Needless to say, for me and a number of others, PPL is the preferred medium for writing programs and serves as an important and enjoyable tool of thought. To me, PPL is rich, highly versatile and easy to use As is the case for most other languages, PPL evokes both adoring remarks from its proponents and the usual scorn from its detractors. In analogy to the process of stellar evolution, if there is such a thing as a ?main sequence? for the life of programming languages, PPL seems well launched on it (though programming languages probably die by fizzling out, not by exploding). Yet PPL is a failure. A few years ago, the vision of extensible languages held by some was that users could rapidly and cheaply extend the base of an extensible language to encompass the data, the operations, the notation and the control natural to many diverse application areas. In short, one was supposed to be able to manufacture personalized languages of reasonable efficiency and substantial utility with great ease just by applying some easily learned extension techniques. It was thought that just as programmers decree the organization of processes (by defining and calling subroutines),they should also decree appropriate organizations for data and for notation, in order to attain more clarity and efficiency.
          in [ACM] SIGPLAN Notices 6(12) December 1971 Proceedings of the international symposium on Extensible languages Grenoble, France 1971 view details
  • Rosen, S. "Programming Systems and Languages 1965-1975" view details Abstract: In spite of impressive gains by PL/I, Fortran and Cobol remain the languages in which most of the world's production programs are written and will remain so into the foreseeable future. There is a great deal of theoretical interest in Algol 68 and in extensible languages, but so far at least they have had little practical impact. Problem-oriented languages may very well become the most important language development area in the next five to ten years. In the operating system area all major computer manufacturers set out to produce very ambitious multiprogramming systems, and they all ran into similar problems. A number of university projects, though not directly comparable to those of the manufacturers, have contributed greatly to a better understanding of operating system principles. Important trends include the increased interest in the development of system measurement and evaluation techniques, and increased use of microprogramming for some programming system functions. DOI
          in [ACM] CACM 15(07) (July 1972) view details
  • Sammet, Jean E. "Roster of Programming Languages for 1973" p147 view details
          in ACM Computing Reviews 15(04) April 1974 view details
  • Stock, Marylene and Stock, Karl F. "Bibliography of Programming Languages: Books, User Manuals and Articles from PLANKALKUL to PL/I" Verlag Dokumentation, Pullach/Munchen 1973 475 view details Abstract: PREFACE  AND  INTRODUCTION
    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 ACM Computing Reviews 15(04) April 1974 view details
  • Taft, Edward A. and Standish, Thomas A. "PPL User's Manual Technical Report", Harvard University, September 1974 view details
          in ACM Computing Reviews 15(04) April 1974 view details
  • Sammet, Jean E "Roster of programming languages for 1976-77" pp56-85 view details
          in SIGPLAN Notices 13(11) Nov 1978 view details
  • Kupka, I. and Wilsing, N. "Conversational Languages" John Wiley, 1980 view details
          in SIGPLAN Notices 13(11) Nov 1978 view details