4 ms·

> was at PARC in 01976, and what inspired him most there was Mesa Wirth was twice at PARC. In his HOPL3 paper he writes in section 4 "From Modula to Oberon":

by Rochus 5y ago

> was at PARC in 01976, and what inspired him most there was Mesa Wirth was twice at PARC. In his HOPL3 paper he writes in section 4 "From Modula to Oberon": "As my sabbatical year at Xerox in 1976/77 had inspired me to design the personal workstation Lilith in conjunction with Modula-2, my second stay in 1984/85 provided the necessary inspiration and motivation for the language and operating system Oberon [29, 30]. Xerox PARC ’s Cedar system for its extremely powerful Dorado computer was based on the windows concept developed also at PARC for Smalltalk. [...] Thus the idea was born of gaining first-hand experience by designing such a modern operating system on my own, with Cedar as the primary source of ideas." > IIRC Griesemer did his dissertation under Wirth at ETH His supervisor was actually Prof. Mössenböck, the author of Oberon-2 (from which Go inherited its type-bound procedure syntax), see https://www.research-collection.ethz.ch/bitstream/handle/20.500.11850/141363/eth-39157-01.pdf https://www.research-collection.ethz.ch/bitstream/handle/20....

kragen 5y ago
Thank you very much for the corrections! I haven't read HOPL3 yet, but he probably said similar things in the Oberon book and I just misremembered it. Apologies for misleading readers!
- Rochus 5y ago
  In fact, I'd be very interested to know what Wirth thinks about Smalltalk; I haven't read a statement from him about it anywhere, or heard anything from him about it in the many interviews; interestingly, Kay asked him a question at the Turing Price lecture and even introduced himself by name, and you didn't get the impression that Wirth knew him. I also find it remarkable that while Wirth refers to the windows concept and Smalltalk in the HOPL paper, which was written as recently as 2005, Cedar does not use overlapping windows at all, but rather - like the Oberon system - a tiling window manager; the Oberon user interface looks very similar to Cedar and has little resemblance to the Smalltalk-80 user interface.
  - scroot 5y ago
    > In fact, I'd be very interested to know what Wirth thinks about Smalltalk; I haven't read a statement from him about it anywhere, or heard anything from him about it in the many interviews I'd be interested to know as well. It might be worth writing him a physical letter asking about it. There is a mailing address for his department at ETH here (https://people.inf.ethz.ch/wirth/index.html https://people.inf.ethz.ch/wirth/index.html) and I'm willing to bet they know how to forward him correspondence.
    - Rochus 5y ago
      His home address and phone number are even in the phonebook, but I don't consider myself or the subject important enough to bother him with it. But maybe someone else here has insider information. That said, there's plenty of circumstantial evidence that he either didn't know Smalltalk in the nineties or didn't think it was worth mentioning. After all, Xerox themselves did not use Smalltalk in their products either, and even at PARC the other teams tended to work with BCPL or Mesa rather than Smalltalk. I read an interview with Larry Tesler where he describes that for a demonstration of a Smalltalk application they had to fast forward the movie so that the menus would pop up fast enough. Not surprisingly, Tesler then brought Object Pascal to life at Apple in collaboration with Wirth, instead of using Smalltalk as he had in his previous job (even though Apple had a license - that was used nota bene later for Squeak).
  - i_don_t_know 5y ago
    There's a hint of what he thinks about Smalltalk in his book "Programming with Oberon" (co-authored with Martin Reiser). See sections 12.6.1 and, in particular, 12.6.2 (pages 236-239): https://people.inf.ethz.ch/wirth/ProgInOberonWR.pdf https://people.inf.ethz.ch/wirth/ProgInOberonWR.pdf
    - kragen 5y ago
      §§12.6.1–2 are on pp. 253/338 to 256/338. Initially I went to the wrong pages. Definitely worth a read. Interestingly his point (3) on p.219 (236/338) ("Within the text of a specific action procedure, a regional type guard is required to allow access to the state variables defined in the extension of the base type") was precisely Abadí and Cardelli's motivation for defining the ς-calculus. This limitation means that Oberon's type system is insufficient to statically guarantee the safety of object methods ("action procedures") and this is an obviously desirable thing. He mentions another similar limitation on the Oberon type system on p. 237 (254/338): "The fact that the compiler cannot check whether a message is ‘understood by the object’ may be an advantage or a disadvantage, depending on the type of the application."

by Rochus 5y ago

kragen 5y ago

Thank you very much for the corrections! I haven't read HOPL3 yet, but he probably said similar things in the Oberon book and I just misremembered it. Apologies for misleading readers!

Rochus 5y ago
In fact, I'd be very interested to know what Wirth thinks about Smalltalk; I haven't read a statement from him about it anywhere, or heard anything from him about it in the many interviews; interestingly, Kay asked him a question at the Turing Price lecture and even introduced himself by name, and you didn't get the impression that Wirth knew him. I also find it remarkable that while Wirth refers to the windows concept and Smalltalk in the HOPL paper, which was written as recently as 2005, Cedar does not use overlapping windows at all, but rather - like the Oberon system - a tiling window manager; the Oberon user interface looks very similar to Cedar and has little resemblance to the Smalltalk-80 user interface.
- scroot 5y ago
  > In fact, I'd be very interested to know what Wirth thinks about Smalltalk; I haven't read a statement from him about it anywhere, or heard anything from him about it in the many interviews I'd be interested to know as well. It might be worth writing him a physical letter asking about it. There is a mailing address for his department at ETH here (https://people.inf.ethz.ch/wirth/index.html https://people.inf.ethz.ch/wirth/index.html) and I'm willing to bet they know how to forward him correspondence.
  - Rochus 5y ago
    His home address and phone number are even in the phonebook, but I don't consider myself or the subject important enough to bother him with it. But maybe someone else here has insider information. That said, there's plenty of circumstantial evidence that he either didn't know Smalltalk in the nineties or didn't think it was worth mentioning. After all, Xerox themselves did not use Smalltalk in their products either, and even at PARC the other teams tended to work with BCPL or Mesa rather than Smalltalk. I read an interview with Larry Tesler where he describes that for a demonstration of a Smalltalk application they had to fast forward the movie so that the menus would pop up fast enough. Not surprisingly, Tesler then brought Object Pascal to life at Apple in collaboration with Wirth, instead of using Smalltalk as he had in his previous job (even though Apple had a license - that was used nota bene later for Squeak).
- i_don_t_know 5y ago
  There's a hint of what he thinks about Smalltalk in his book "Programming with Oberon" (co-authored with Martin Reiser). See sections 12.6.1 and, in particular, 12.6.2 (pages 236-239): https://people.inf.ethz.ch/wirth/ProgInOberonWR.pdf https://people.inf.ethz.ch/wirth/ProgInOberonWR.pdf
  - kragen 5y ago
    §§12.6.1–2 are on pp. 253/338 to 256/338. Initially I went to the wrong pages. Definitely worth a read. Interestingly his point (3) on p.219 (236/338) ("Within the text of a specific action procedure, a regional type guard is required to allow access to the state variables defined in the extension of the base type") was precisely Abadí and Cardelli's motivation for defining the ς-calculus. This limitation means that Oberon's type system is insufficient to statically guarantee the safety of object methods ("action procedures") and this is an obviously desirable thing. He mentions another similar limitation on the Oberon type system on p. 237 (254/338): "The fact that the compiler cannot check whether a message is ‘understood by the object’ may be an advantage or a disadvantage, depending on the type of the application."