ELAN (programming language)
The programming language ELAN ( E ducational LAN guage ) was developed in 1976 at the Technical University of Berlin and the GMD research center for information technology at the suggestion of the working group for school language. At the Technical University of Berlin (Department of Software Technology), a research project was carried out in collaboration with Nixdorf Computer with the aim of being able to use ELAN in schools. This ELAN compiler was developed using the CDL2 language.
The basis of ELAN is the SLAN language family, which was also created at the Technical University of Berlin. The aim of the development was the easy learnability and the usability in schools.
The features that are intended to facilitate learning top-down programming include, for example, the so-called refinements . The program code first describes in clear text what is to be done; these descriptions are explained below.
Example:
werte vorbelegen; rechnen.
werte vorbelegen: INT CONST a := 27; INT CONST b := 15.
rechnen: INT CONST antwort := a + b.
PROC eine prozedur (TEXT CONST txt):
IF txt = "a" THEN
putline ("a wurde übergeben");
ELIF txt = "b" THEN
putline ("b wurde übergeben");
ELSE
putline ("etwas anderes wurde übergeben");
FI;
END PROC eine prozedur;
These refinements are unknown in other programming languages and can best be compared with parameterless macros . If refinements are used skillfully, ELAN programs are largely self-explanatory.
There was already extensive modularization in the language, as will later be found in languages such as Java .
distribution
Most of the operating systems L2 and L3 were written in ELAN. L2 is also known under the name EUMEL ( " E xtendable multi U ser M icroprocessor EL AN System").
One of the first schools to include ELAN in their computer science classes were the Ceciliengymnasium in Bielefeld before 1978 and the Max Planck Gymnasium from 1980. In the same year, an ELAN-based two-place system was set up at the Carl-Duisberg-Gymnasium in Wuppertal , where pupils learned to program in ELAN. From 1981 ELAN was taught on a 5-place L2 system in computer science lessons at the Wesermünde high school in Bremerhaven . At the Aspe school center (Rudolph-Brandes-Gymnasium) in Bad Salzuflen and at the Dietrich-Bonhoeffer-Gymnasium in Wiehl , multi-user systems ( multiuser ) with several terminals and central PCs under EUMEL were used for programming training with ELAN for several years from around 1982 operated. In the 1980s, computer science was also taught at the Helmholtz grammar school and at the Collegium Josephinum in Bonn , at the Freiherr vom Stein grammar school in Kleve , at the Warstade grammar school in Hemmoor and at the Otterndorf grammar school in Otterndorf in the 1980s. Until the end of the 1980s, ELAN was taught in vocational schools for business as part of IT lessons; for example at the vocational schools in Einbeck .
At the end of the 1980s a research project was carried out at the TU Berlin together with the NIXDORF company. Bernhard Gramberg developed his own operating system for the 8870 / U and implemented ELAN on this research. This enabled NIXDORF to participate in the tender for new school computers that was ongoing at the time. As part of this research project, teacher training for Berlin schools with ELAN has been carried out over the years at the TU Berlin.
ELAN is still in use in various applications today (see L3 ).
literature
- G. Hommel, J. Jäckel, S. Jähnichen, K. Kleine, W. Koch, CHA Koster: ELAN language description . Academic Publishing Society, Wiesbaden 1979, ISBN 3400003840 .
- Rainer Hahn, Peter Stock: ELAN manual . 2., corr. Edition. Akademische Verlagsgesellschaft, Wiesbaden 1982, ISBN 3-400-00499-5 (First edition 1979: archive.org [ DjVu ; 1.9 MB ; accessed on May 4, 2020]).
- LH Klingen, J. Liedtke: Programming with ELAN . Teubner Verlag, Stuttgart 1983, ISBN 3519025078 .
- LH Klingen, J. Liedtke: ELAN in 100 examples . Teubner Verlag, Stuttgart 1985, ISBN 3519025213 .
- CHA Koster: Top-Down Programming with Elan . Ellis Horwood, 1987, ISBN 0745801870 .
See also
Web links
- ELAN implementation by the University of Nijmegen
- University of Dresden to ELAN
- Introduction to ELAN from the L3 user manual at the University of Dresden
Remarks
- ↑ Compiler Description Language 2 (English)