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2Michael Franz

 purpose of “marketing” his subsequent ideas. Indeed, he even refrained from givinghis later programming-language creations names such as “Pascal-2”, “Pascal Plus”,or “Pascal-2000” but instead opted first for “Modula”, and then “Oberon”. Both of these languages would probably have been considerably more successful if theconnection to the Pascal legacy had been made in their name

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, but this would haverun counter to Wirth’s view that a marketer he is not.Unfortunately, in an academic culture of increasingly flatulent self-promotion,such modesty eventually almost inevitably leads to a certain degree of self-imposedobscurity. In Wirth’s case, the world continued to clamor for “more Pascal” for quitea while, but Wirth had long moved on to new horizons and more or less ignoredthese requests. Eventually, the world lost interest, and it, too, moved on to newhorizons, which unfortunately were not always compatible with Pascal and itssuccessor languages.The principal reason why Wirth did not immediately respond to clamors for “more Pascal” was of course simply that he did

not 

view himself primarily as a“language guy”. Indeed, Wirth’s publication record quite conclusively demonstratesthat his talent has always been much broader and focused chiefly at the

 system

level.Twice in his career, Wirth was instrumental in building a complete computer system“from scratch”, each consisting of a hardware platform, a modular operating systemand related systems-level software such as compilers and assemblers, and also alimited amount of highly innovative application software.Both of these systems,

Lilith

/Medos/Modula

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in 1981, and Ceres/

Oberon

in1988 were years ahead of their time and could at the point of their inception berivalled by only a small number of far more complex research systems beingdeveloped at places such as Xerox’ Palo Alto Research Laboratory

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. For example,the Oberon System of almost ten years ago anticipated such innovations as ahypertext-based user interface, living “applets” embedded within documents, target-machine independent mobile code, and document-centric computing. And Oberon provided not just the vision, but also executed that vision in a robust implementation 

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Wirth himself makes this observation in [Wir93].

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The Lilith/Medos/Modula-2 system is usually summarily referred to as the “Lilith system” while the“Ceres/Oberon” system is commonly known as “The Oberon System”. This probably reflects thegreater relative importance of the hardware aspects at the time of Lilith, as well as the fact thatOberon soon emancipated itself of the Ceres hardware platform by being ported to several alternativearchitectures as well.

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The Lilith and Oberon projects were in fact both inspired by systems that Wirth had encountered atXerox PARC, namely the Mesa and Cedar systems. Wirth succeeded in replicating many of the keycharacteristics of these advanced systems with considerably less effort, achieving this remarkablyreduction in complexity to some extent by leaving out some inherently complex features, such as preemptive multitasking. As a consequence, comparisons with the much larger research systemsexisting at the time aren’t entirely fair.