SIMULA INFORMATION

Jan Scheutjens
1992-05-31

If you want to do object-oriented programming you definitely should have a look at SIMULA. SIMULA is the first and still the most advanced object-oriented programming language available on a wide variety of machines including the Atari ST.
SIMULA has been in general use for twenty years and the soundness of its philosophical foundation has been thoroughly established.

SIMULA in a Nutshell

Conventional general-purpose algorithmic capability in the style of ALGOL 60.
Object-oriented programming (classes) encompassing encapsulation, inheritance, information hiding, autonomous activity and strong typing, supporting the concepts of modularisation, generalisation, specialisation, abstraction, polymorphism and pseudo-parallelism.
Basic features for manipulating text strings.
File concept supporting sequential and direct access methods for byte- and record-structured files.
Large repertoire of utility functions.
Features supporting 2-way linked lists. More complicated list structures such as trees and lattices are easily constructed from the basic class facilities.
Features supporting discrete event simulation in various styles including the object-oriented process view.

It should be emphasised that although in many quarters SIMULA is best known for its simulation features, it is a truly general-purpose language in the widest sense and was the inspiration for almost all developments in the field of object-oriented programming. For a growing number of users the name is becoming an acronym for SIMple Universal LAnguage.

What you get with each SIMULA system

Object oriented programming. A typical SIMULA program execution consists of a set of interacting processes or objects. Objects are incarnations of some prototype or class, generated during the execution of the program. Programs written in SIMULA in the object-oriented style preserve more accurately the identities and relationships of the functional entities occurring naturally in the computation.
Strong typing, checked mostly at compile time, ensuring that objects are manipulated in a manner consistent with their specification.
Objects may act independently of each other in “quasi- parallel”. This enables the class objects to act as coroutines, so that the autonomous activity of any object may be temporarily suspended, later to be resumed at the exact point of suspension. Coroutines facilitate a faithful representation of systems composed of not only passive objects but also active ones in which distinct bursts of activity are tightly coupled in the notion of a coherent process. This feature is an extra dimension to those commonly associated with object-oriented languages and is only recently beginning to appear in some of the newer ones.
List processing. The standard class “Simset” may be invoked to add list processing capabilities to the basic language features. The programmer will then have tools for the efficient manipulation of common aggregate information structures, including queues, dequeues, stacks and cyclic buffers. The facilities of Simset can be further refined for more specialised purposes.
Simulation. Application of the standard class “Simulation” converts SIMULA into a powerful tool for discrete event simulation in a style which preserves in the model the inherent structure of the system under study. Object-oriented programming originated in process-oriented simulation and simulation in SIMULA is the epitome of the object-oriented paradigm.
Powerful text handling, dynamic arrays, flexible file handling, etc.
Modularisation. Separate compilation of classes and procedures is an integral part of the language. The strong typing extends to separately compiled modules allowing the construction of large SIMULA systems to be partitioned into subtasks, which may be assigned to different work groups without fear of undetected incompatibilities.
Garbage collection. Languages without automatic object storage administration cause their practitioners enormous problems in determining the life span of objects. This leads either to the premature demise of useful objects or to the silting up of memory resulting in unwanted and sometimes irreproducible situations which defy diagnosis. SIMULA has automatic garbage collection, eliminating intractable problems of this nature.
Portability. SIMULA has a rigid standard definition and programs are highly portable between different computer systems (source code compatibility).

Books on SIMULA

The most recent version is stored on the Simula database on Bitnet and Internet.
On Bitnet get a copy by sending GET SIMULA BOOKS as first line of your email
to Listserv@DERAN.
On Internet use Gopher or ftp to ftp.fenk.wau.nl and look in the
pub/simula directory.

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The Standard:

SIMULA Standard. DATA processing - Programming languages - SIMULA.
  Swedish Standard SS 63 61 14,
  SIS, Box 3295, Stockholm, Sweden, (1987).
  ISBN 91-7162-234-9


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Textbooks on SIMULA:

SIMULA begin
  Graham M. Birtwistle, Ole-Johan Dahl, Bjoern Myhrhaug, and Kristen Nygaard.
  Petrocelli/Charter, New York (1975).
  ISBN 0-88405-340-7.

  Studentlitteratur, Lund, Sweden (1973)
  ISBN 91-44-06211-7.

  Bratt Institut fur Neues Lernen, Goch, GDR

  Chartwell-Bratt Ltd., Bromley, England.

  Auerbach, U.S.A.

Introduction to SIMULA 67
  Guenther Lamprecht
  Vieweg Verlag, Braunschwig,
  Wiesbaden (1981)

SIMULA - Einfuehrung in die Programmiersprache.
  Guenther Lamprecht
  Vieweg Verlag, Braunschweig,
  Wiesbaden, 3. neubearbeitete Auflage (1988) (In German).
  ISBN 3-528-23321-4.

Programmering i Simula
  Goran Eriksson & Per Holm.
  Lund Institute of Technology
  Computer Science Department
  Box 118, S-22100 Lund, Sweden (1979).  (In Swedisch.)

Grundlaggende programmering i SIMULA
  Staffan Romberger & Yngve Sundblad.
  Tekniske Hogskolelitteratur, Stockholm, Sweden (1979). (In Swedisch.)

Fortsatt programmering i SIMULA
  Staffan Romberger & Yngve Sundblad.
  Tekniske Hogskolelitteratur, Stockholm, Sweden (1979). (In Swedisch.)

Simula-Simulation
  Karoly Siklosi
  Tekniske Hogskolelitteratur, Stockholm, Sweden (1977). (In Swedisch.)

Systematisk Programmering
  Bjorn Kirkerud.
  Universitetsforlag, Oslo, Norway. (In Norwegian.)

SIMULA, Ein Einfuhrung
  Helmut Rohlfing.
  Bibliographisches Institut AG, Mannheim, FDR (1973). (In German.)

SIMULA, stap voor stap
  Jaap Hoogakker
  Computercentrum Groningen, The Netherlands. (In Dutch.)

SIMULA-voorbeelden, stap na stap
  Jaap Hoogakker
  Computercentrum Groningen, The Netherlands. (In Dutch.)

La Programmation en SIMULA
  Jean Vaucher
  University of Montreal, Canada. (In French.)

Programovani v jazyku SIMULA 67
  Zdenek Benda & Jan Staudek.
  SNTL, Prague, Czechoslovakia (1978). (In Czech.)

SIMULA 67
  H. Oktaba & W. Ratajczak.
  Wydawnictwo Naukowo-Techniczne, Warsaw, Poland (1980). (In Polish.)

SIMULA Programming
  A.N. Andrianov, S.P. Bychov & A.L. Khoroshilov.
  Physical Mathematical Literature Service, Moscow, USSR (1985). (In Russian.)

Do it with SIMULA
  P. Jedlovszky.
  COMPUDRUG International,
  Laxenburgerstr. 49/7/15, A-1100 Vienna, Austria (1986).

An Introduction to Programming in SIMULA
  R.J. Pooley.
  Blackwell Scientific Publications,
  Oxford, London, Edinburgh, Boston, Palo Alto, Melbourne (1987).
  ISBN 0-632-01611-6.
  ISBN 0-632-01422-9 Pbk

SIMULA 67 Lecture Notes
  Laborczi, Zoltan.
  Computer Application Research Institute,
  Budapest, Hungary, Publication No. 13 (1976). (In Hungarian.)

Object-Oriented Programming with SIMULA
  Bjoern Kirkerud.
  International Computer Science Series.
  Addison- Wesley Publishing Co. (1989).
  ISBN 0-201-17574-6.



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Textbooks on SIMULA:

[BDMN73]  Graham M. Birtwistle, Ole-Johan Dahl, Bjoern Myhrhaug,
          and Kristen Nygaard. SIMULA BEGIN. Studentlitteratur,
          Lund, Sweden, 1973. ISBN 91-44-06211-7. Also published
          by Bratt Institut fuer neues Lernen, Goch, GDR and
          Chartwell-Bratt Ltd., Bromley, England.

[Jed86]   P. Jedlovzky. Do it with SIMULA. COMPUDRUG International,
          Laxenburgerstr. 49/7/15, A-1100 Wien, Austria, 1986.

[Poo87]   R. J. Pooley. An Introduction to Programming in SIMULA.
          Blackwell Scientific Publications, Oxford, 1987.
          ISBN 0-632-01611-6 resp. 0-632-01422-9 (pbk.).

[Lam88]   Guenther Lamprecht. SIMULA - Einfuehrung in die
          Programmiersprache. Vieweg Verlag, Braunschweig,
          Wiesbaden, 3. neubearbeitete Auflage, 1988.
          ISBN 3-528-23321-4. (In German, also available in
          English)

[Kir89]   Bjoern Kirkerud. Object-Oriented Programming with
          SIMULA. International Computer Science Series. Addison-
          Wesley Publishing Co., 1989.  ISBN 0-201-17574-6.

Textbooks on Simulation:

[Fra77]   W. R. Franta. The process view of simulation. Elsevier
          North-Holland, New-York, 1977. Also published by North-
          Holland, Netherlands.

[Bir79]   Graham M. Birtwistle. DEMOS - Discrete Event Modelling
          on SIMULA.  MacMillan Press, London, Basingstoke, 1979.
          ISBN 0-333-32881-8.

[Mit82]   I. Mitrani. Simulation Techniques for discrete event
          systems. Cambridge University Press, 1982.

[Kre86]   Wolfgang Kreutzer. System Simulation Programming Styles
          and Languages. Addison-Wesley Publishing Co., 1986.


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Textbooks on Simulation

DEMOS - Discrete Event Modelling on SIMULA
  Graham M. Birtwistle
  MacMillan Press London, Basingstoke (1979).
  ISBN 0-333-32881-8.

The Process View of Simulation
  W.R. franta.
  Elsevier North-Holland, New York (1977)
  and North-Holland Publishing Company, Netherlands (1977).

Simulation Techniques for Discrete Event systems.
  I. Mitrani.
  Cambridge University Press (1982).

System Simulation Programming Styles and Languages.
  Wolfgang Kreutzer.
  Addison-Wesley Publishing Co. (1986).

CADSIM users guide and reference manual
  Sim, R.J.W.
  Dept. of Computing and Control
  Imperial College, London SW7 2B2, (1975).

An introduction to combined continous
  and discrete event process simulation in SIMULA.
  Sim, R.J.W, and Cunningham, R.J.
  Dept. of Computing and Control
  Imperial College, London SW7 2B2, (1976).

DYNA-SIM, System-Dynamic models programmed in SIMULA
  Peterzens, Per G.
  Norwegian Defence Research Establishment
  Postbox 25
  2007 Kjeller, Norway, (1982). (In Norwegian)

  Abstract: A method for the programming of System-dynamic models
  (computed differential equations- J.W. Forrester models) is described.
  The method, called DYNA-SIM, is implemented as a class in the SIMULA
  programming language, and makes possible a combination of continuous and
  discrete simulation. The syntax of of DYNA-SIM is quite similar to the
  well-known DYNAMO-language.

  The principles of the method is described. The syntax rules for the
  programming of a user model is given. An example of combined use of
  continuous and discrete simulation is shown.

DYNAMO in SIMULA 67, a rough outline of a simple implementation.
  Hegna, H.
  Norwegian Computing Center
  Postbox 114 Blindern
  0314 Oslo 3, Norway, (1974).